**Ask a monkey a physics question thread**

[CoccoBill]

Thanks for the replies, sorry took a while to comment. Yeah that's some weird stuff, I'm not sure I'm any closer to intuitive understanding of torque.

Another, completely unrelated, thing. Ever since years ago watching some documentary about the scale of atoms, the relative distance between electrons and the nuclei, I've been wondering about this but never been able to find any explanation that I could understand. If you exert enough outside pressure to the electrons to squeeze them into the nucleus you're breaking the electron degenerative pressure, and if you have enough mass together in practise this is what happens when a star collapses into a white dwarf, right? If then you keep applying more force, enough to force the electrons and protons to combine and create neutrons (the Chandrasekhar limit?), you're left with a neutron star? Still not satisfied, you keep exerting more force (and adding mass) to collapse the neutrons (the Tolman–Oppenheimer–Volkoff limit?) you end up with a black hole or something silly like a quark star?

[BananaStand]

What's the latest on the quantem enigma?

Is there any progress or viable theories on why matter behaves differently based on whether or not you're watching it?

[OngBonga]

Thanks for the replies, sorry took a while to comment. Yeah that's some weird stuff, I'm not sure I'm any closer to intuitive understanding of torque.

Torque is the force applied to a wrench, multiplied by the length of the wrench (and the angle of force, but let's not think about changing that, just stick to a nice perpendicular 90 degrees). If you apply a force, the nut turns. If you increase the length of the wrench, but apply the same force, the nut turns quicker. Why? Because we're getting more work for the force... torque.

I guess it's easy to say this and accept it as fact, because we know it's easier to turn nuts with longer spanners, but it's not so easy to understand why we're getting more work for our force.

The easiest way to imagine torque that I can think of is to think of a scale. First, imagine it balanced. Now put a 2kg weight on one side, and a 1 kg weight on the other, but twice the distance from the centre as the 2kg weight is. The scales remain balanced. Why? Torque. The rotational force around the centre of balance applied by the 2kg weight equals the rotational force applied by the 1kg weight. Torque is the measure of rotational force, the torques are balanced in this example, and as such the scales are balanced.

Things on a scale appear "heavier" the further they are from the the centre of balance. If you apply this concept to a spanner and nut, then you're getting more "weight" from your work with a long spanner than you get with a smaller one.

[OngBonga]

I came here because I wanted to ask a question...

My computer room is approx 2x2x2 meters, and has no windows. During the recent good weather we had, the temperature in this room was getting up to 35 degrees, and was too hot for my computer, which would crash due to "thermal event". A fan pointing directly at the comp deals with this, but it's still uncomfortable sitting in 35 degrees. I can't afford a AC unit, so I'm left wondering how much I can cool this room using evaporation methods.

Are there any tables I can refer to that will tell me how much evaporation needs to take place for a set target in reduction in temperature? Obviously I know humidity is an important factor, I might be able to borrow a dehumidifier through the summer so that might be controllable despite the lack of ventilation. So... at 50% RH and 35 degrees celcius in 8 cubic meters of air, can I get a reduction of 10 degrees by evaporation alone?

[MadMojoMonkey]

Thanks for the replies, sorry took a while to comment. Yeah that's some weird stuff, I'm not sure I'm any closer to intuitive understanding of torque.

You just gotta keep on it. It's a classical phenomenon (unlike QM and GR), so as a general rule it will eventually be intuitive to you if you keep thinking about it.

Another, completely unrelated, thing. Ever since years ago watching some documentary about the scale of atoms, the relative distance between electrons and the nuclei, I've been wondering about this but never been able to find any explanation that I could understand.

Well, let's see...

If you exert enough outside pressure to the electrons to squeeze them into the nucleus you're breaking the electron degenerative pressure, and if you have enough mass together in practise this is what happens when a star collapses into a white dwarf, right?

Yes, that's right. Except "into the nucleus" is terribly misleading. Electrons already spend time inside the nucleus, just not much on average.

The degeneracy pressure is a consequence of squeezing electrons close to each other, not to a nucleus.

If then you keep applying more force, enough to force the electrons and protons to combine and create neutrons (the Chandrasekhar limit?), you're left with a neutron star?

Yes.

Be cautioned against thinking that a neutron is somehow a proton and an electron stuck together. That's not the case. The electron is annihilated in the process of changing the proton into a neutron. They aren't really "combined" in that sense.

Still not satisfied, you keep exerting more force (and adding mass) to collapse the neutrons (the Tolman–Oppenheimer–Volkoff limit?) you end up with a black hole or something silly like a quark star?

Yes again... but this one isn't really a question, now, is it?

[MadMojoMonkey]

What's the latest on the quantem enigma?

What's that?
(google search)
Oh... I'm pretty sure that's a misunderstanding of what physics says because it's being interpreted by non-physicists and the physicists didn't make it clear what their definitions are.

Is there any progress or viable theories on why matter behaves differently based on whether or not you're watching it?

I'm guessing the confusion stems from the typical quantum physicist's use of the word "observe" to be interchangeable with "interacts with."

The behavior of matter has nothing to do with whether a person or consciousness is watching it.

It simply states that when matter isn't interacting with anything, it behaves in one way, and when it is interacting with other stuff, it behaves in another way. Both patterns of behavior are well defined within the statistical limits of observation and theory.

[MadMojoMonkey]

It takes 40.66 kJ/mol of water to turn it from 100 degree water into 100 degree water vapor.
1 mol of H2O is (2*1g/mol + 1*16g/mol = ) 18 g/mol. Since 1 cc of water has a mass of 1 g, a mol of water is 18 cc.
So evaporating 18 cc of water will require the water to absorb 40.66 kJ of energy

The density of dry air is 1.225 kg/m^3.
Your 8 m^3 room has (8 m^3 * 1.225 kg/m^3 = ) 9.8 kg of air in it.

The specific heat of air is 1.005 kJ/kg*K.
You want to change the temperature of a 9.8 kg of air, so 1.005 kJ/kg*K * 9.8 kg = 9.849 kJ/K.

You want to lower the temperature by 10 C (which equals 10 K), so 9.849 kJ/K * 10 K = 98.49 kJ

This is a lottle more than double the energy required to evaporate 18cc of water, so evaporating a bit more than 36 cc, maybe 40 cc of water should do the trick.
This is a 1-time cost. Once you cool the room, you don't have to do so again... so long as there are no heat sources in the room, and it is perfectly insulated from heat transfer through the walls / doors.


In practice, you sitting there doing no exercise is close to ~75 - 100 Watts of power produced. Most of that power is heating the room.
That's another ~0.1 kJ per second that you need to dissipate. To do this, you need to evaporate another ~27 cc per minute.
Plus the computer is also a heat source.

[BananaStand]

What's that?

The behavior of matter has nothing to do with whether a person or consciousness is watching it.

Hmm, that's not how it was explained to me. Caution: Netflix-documentary style science ahead.

Imagine a solid wall. A few feet in front of it, you have another wall with two holes cut out of it. You stand in front of both walls and throw baseballs. Some of your baseballs will go through the holes in the outer wall, and hit the solid wall behind it. If we marked the points of contact, the solid wall in back would have two hole-shaped regions where it was struck by baseballs, and the rest of the wall would be untouched.

Now imagine instead of baseballs you launched something that travels in a wave, like sound, toward the walls. The sound waves would hit all over the outer wall, and some of the sound wave would make its way through the holes. Since there two holes, the sound wave is now emanating from two points on the outer wall and travelling toward the solid wall. Again, if you could mark the points of impact where the sound wave meets the solid wall, you'd have a completely different pattern than the baseball example.

So particles traveling through holes in the outer wall will only impact the solid wall in certain hole-shaped regions that align with the outer wall. Waves travelling through the holes will split up, emanate through two holes, and the two new waves will overlap each other somewhat before they hit the solid wall. And if you could mark their impacts with the solid wall, it would make a different pattern than the baseballs. Regions where the waves overlapped got double-impact, and places that only got hit by one wave had less impact. On the show it looked like vertical lines.

So what should light do?

It's not a wave, it's photons. Particles with a finite observable size and shape. Logic tells you that they should behave like the baseballs, and only make impact with the solid wall in the regions that align with the holes on the outer wall.

Except that's not what happens. Light hits the solid wall and makes a pattern as if it were a wave

So scientists saw this and said "What the fuck??" Let's slow this all down, and watch individual photons and see what they do.

So they built some kind of science-y apparatus that let's them see individual particles and they watched what happens when photons are fired through this outer wall with holes in it.

Well jiminy cricket.....when they watched the photons move through the holes, they impacted the solid wall in only specific regions. Just like baseballs.

Then they turned around and ran the experiment again, without watching, and found that the light acted like a wave again.

So they tried again, this time watching, and......baseball pattern

Close your eyes and try again......wave pattern

Now open them and do it one more time.....baseball pattern

What's up with that?

EDIT: This link explains it a little better than I did
https://motherboard.vice.com/en_us/a...ssical-world-2

[CoccoBill]

I guess I more meant that the effects of applied torque can be unintuitive, not the force itself. Hm so in car specs, torque is the rotational force applied to the crankshaft, and horsepower is the amount of work, or transfer of energy, the engine can do in a set time?

And yeah on that atom squeezing stuff was I was more looking for a confirmation if I got it right, no question there if it was in the ballpark.

The degeneracy pressure is a consequence of squeezing electrons close to each other, not to a nucleus.

Alrighty then, not as simple as I expected, not surprisingly. In the visualizations it's always stressed how far the electrons actually are from the nucleus and how much empty space there is in between. If matter is mostly nothing, it just led me to think what would happen if you squeeze matter enough, and just picturing applying enough force to pack all of the atoms (or nuclei) together, with no empty space in between. I do realize it's not like electrons are just there spinning on perfect orbits around the nucleus like earth around the sun, but they're all over the place, even at the same time. That would have just been such a satisfactory intuitive explanation. So what does exactly happen when the force applied is nearing the Chandrasekhar limit, is the distance between the electrons and the nuclei being limited or how do they end up butting heads?

[MadMojoMonkey]

So what should light do?

Weeee!

It's not a wave, it's photons.

Wave = particle = wave = particle
Observations to the contrary reveal a fault in human perception (which I share).
The experimental confirmation of wave-particle duality is ridiculously well established.

Just today, I demonstrated the photoelectric effect which shows the particle nature of photons. Tomorrow I'm demonstrating that exact double-slit experiment you described, showing the wave-nature of photons.

I have Geiger counters which detect Beta radiation (emitted electrons from nuclear decay) as individual particles. I also have a demonstration which shows electrons diffracting like waves when a beam of them is passed through a crystal.

I mean... none of this should really convince you, as it's all hearsay... on the internet, no less... but it's actually not very hard to do some experiments yourself. It takes some equipment and a DIY spirit, but you don't really need expensive stuff to tease out the physics.

photons. Particles with a finite observable size and shape.

Photons are hardly alone on the list of particles which have no known measurable size or shape.
As always with these kind of measurements, it's impossible to prove a 0. There is always measurement uncertainty. You can keep pushing down the maximum size, given that you keep measuring 0, but your resolution isn't infinite. There's always a cutoff where you have to admit that it could be there, but smaller than X.

Quantum particles have fuzzy edges... their positions and momenta are probability fields manifest in moving matter, which obey various uncertainty relations. Even for particles whose size and shape we can measure, e.g. protons and neutrons, these properties are described as probability density functions. I.e. there's a sphere which we call the proton radius, but it really represents some statistical percent chance of finding a proton in that volume, and not the size of a ball which is the proton occupying that volume.

Logic tells you that they should behave like the baseballs, and only make impact with the solid wall in the regions that align with the holes on the outer wall.

When flawless logic yields absurd results, then at least one of the "given" statements of the logic must be false.
Algebra is awesome!

In this case, it's the assumption that "particle" and "wave" are somehow not the same.
The difficult to accept reality is that they are the same, or at least, aspects of the same thing.

Except that's not what happens. Light hits the solid wall and makes a pattern as if it were a wave
So scientists saw this and said "What the fuck??" Let's slow this all down, and watch individual photons and see what they do.
So they built some kind of science-y apparatus that let's them see individual particles and they watched what happens when photons are fired through this outer wall with holes in it.
Well jiminy cricket.....when they watched the photons move through the holes, they impacted the solid wall in only specific regions. Just like baseballs.

"Watched" is in need of defining, here. I don't know what exact experiment you're referencing, but they are all similar in the important respects.

They setup some way to detect which hole the photons passed through. In so doing, the photons' superposition of passing through both holes collapses to a single hole, and it propagates accordingly thereafter.

The "watching" isn't being done by scientists... it's being done by whatever they setup as a detector. All detectors detect by interacting, so it's the detector watching the photons that matters, not the conscious minds which set it up.

Then they turned around and ran the experiment again, without watching, and found that the light acted like a wave again.
So they tried again, this time watching, and......baseball pattern
Close your eyes and try again......wave pattern
Now open them and do it one more time.....baseball pattern

What's up with that?

When the wave function approaches a hole or slit commensurate with its wavelength, weird things happen.
The photons don't technically have to pass through a hole, they just have to pass closer than their wavelength to something to diffract off of it.

The wave function diffracts off of the edges of the hole, and if the hole is small enough, the waves will diffract throughout its opening. However, the quantum weirdness is that no matter how the position wave function spreads out, we never observe the energy of the photon spread out. We only observe single bumps (quanta) of energy, equal to the energy corresponding to that wavelength of light.

It's weird. It defies intuitive understanding.

The diffracting causes the photon's wave function to exist as a superposition of more than one position/momentum pair.
Which means that until it interacts with something, it is spread out over many places, and its momentum is spread out to match how it got there.

If it interacts with the wall, then the wave function collapses will only be where the wave function is not completely destructively interfering with itself. The wave functions are collapsing at the wall, which captures the amalgam of many individual wave function collapses, and the probabilistic nature of their superposition manifests as wave interference they experience at the moment of their observation (by the wall).

If it interacts with something else, prior to the wall, then the spread-out wave function collapses at that interaction and it no longer exists in the particular superposition of states which was set up in passing through the hole.

EDIT: This link explains it a little better than I did
https://motherboard.vice.com/en_us/a...ssical-world-2

This experiment is a little different in that they discuss measuring the photons' positions just prior to one of the slits.
It raises the question of why does the photon which doesn't pass through the detector's slit still not behave as though it passes through both slits?

The answer is the same. Prior to being detected, the photon was in a superposition of states with a spread in it's position and momentum functions. Whether or not the photon was detected at the detector, certain portions of its wave function always passes through the detector. A lack of detection can still have caused a wave function collapse. The portions of the superposed wave function which describe the wave passing through the detector collapsed to nothing. The measurement was made. The photon wasn't there. The rest of that photon's wave function continues on, uncollapsed, and passing definitively through the undetected hole.

[BananaStand]

I don't know dude. That all really sounds like a lot of maybes and excuses.

Still sounds to me like doing the exact same experiment will yield two different results based on whether or not certain parts of that experiment are being observed.

That's spooky fucking shit!

[BananaStand]

It might seem kinda dubious to get your science lessons from Colonel Sanders in a super hero outfit, but this does a way better job of explaining what I was talking about.

[OngBonga]

Still sounds to me like doing the exact same experiment will yield two different results based on whether or not certain parts of that experiment are being observed.

observed = measured

The act of measuring changes the initial conditions. Of course there will yield two different results based on whether or not it was observed. That's not spooky, it's totally intuitive. How do you "meausre" the velocity and location of a particle? Or, more to the point, how do you do this accurately without altering its trajectory and thus changing the conditions? Hint - you can't, see "uncertainty prinicple".

The double slit experiment can be explained by pilot wave theory. I'm not sure what to make of it all, but the basic gist is every particle has an associated wave, and the wave essentially carves out a geomoetric path for the particle to follow. The trajectory of the particle is determined by its initial conditions, at least until we try to measure it, thus changing its trajectory.

[OngBonga]

It takes 40.66 kJ/mol of water...

Thanks for this analysis, I'll get back to you when the weather perks up again and I put this into action!

[OngBonga]

Here's a visualisation of pilot wave theory...

[BananaStand]

The act of measuring changes the initial conditions. Of course there will yield two different results based on whether or not it was observed. That's not spooky, it's totally intuitive.

So I can change the temperature outside by walking outdoors with a thermometer? Sorry, I'm not buying it.

The fact that I can change the behavior of matter in a way that defies the rules of physics, merely by exercising my own consciousness, pretty much proves that I am God.

Or at least, a god

[OngBonga]

So I can change the temperature outside by walking outdoors with a thermometer? Sorry, I'm not buying it.

Sure going outside changes the temperature. I'm assuming you're warmer than the atmosphere. You are therefore lsoing heat to the atmosphere. Just because the average increase in temperature of the atmopshere is a very slight fraction above zero, doesn't mean it is zero.

The fact that I can change the behavior of matter in a way that defies the rules of physics, merely by exercising my own consciousness, pretty much proves that I am God.

You're not defying phsyics, merely observing it.

[OngBonga]

Also, the thermometer itself causes change. It cools the atmopshere, because the mercury has absorbed heat, causing it to expand.

The mercury moving is direct proof that you have changed the initial conditions that you were trying to measure.

Assuming you go from a warm place to a cold place with a thermometer, then you're warming the atmosphere, because the mercury contracts, losing heat to the atmosphere.

It's negligible, but >0, and therefore change.

[BananaStand]

You're not defying phsyics, merely observing it.

Wait but....

The behavior of matter has nothing to do with whether a person or consciousness is watching it

So which is it?

[OngBonga]

I don't see the contradiction.

[OngBonga]

The behavior of matter has nothing to do with whether a person or consciousness is watching it

It's not the act of "watching" that changes behaviour... it's direct interaction. And everything (with mass) is interacting with everything else (with mass) because of gravity.

Matter behaves as it is insrtucted to based on the conditions in which it is exposed to. If you're standing outside with a thermometer, then you're taking heat from the atmopshere in order to measure the temperature of the atmosphere (assuming it's warmer outside than inside). It's changing because you're measuring it. The only way it wouldn't change is if the atmosphere was already exactly the same temperature as the thermometer. And even then, you'd be interacting with the atmosphere in other ways. You'd displaced air, and therefore changed the airflow of the atmopshere. Again, the most negligible effect one can imagine, but non-zero.

The idea you're "defying" physics is fundamentally flawed. One can't defy phsyics. If it appears you have done, then you've either discovered new laws of phsyics, or you took a bad measurement.

[OngBonga]

Even a case of a police officer firing a beam at a car to determine its speed... that's causing change. The photon hits the car, the car absorbs evergy, and the conditions have changed (albeit in an immeasureable way).

When you realise that in order to measure the velocity and trajectory of a partcle, or even a large physical object such as the moon, one needs to at the very least fire photons at it, then you can start to see that you're changing the conditions in which the object you're measuring was intitially subject to. Yes, in a tiny manner, and for all practical purposes on the macro scale, the change is zero. But it's not actually zero. When we get to the quantum level, well it becomes much less nelgigible.

[OngBonga]

I suppose the act of "watching" does actually cause change. Your posture is causing light to scatter in certain ways. If you have to move to view something, then you're changing the way in which light scatters, and therefore changing the amount of energy being absorbed by whatever it is you're observing. So yes, phsyically looking at something causes change. But that's the same interaction as firing a photon, measuring gravity, whatever.

The relationship between interaction is ludicrously complex, because there's probably over a googolplex of particles all simultaneously interacting with each other.

Our conciousness throws something into the mix... if we assume we have free will, then the universe is essentially shaped by the decisions that conscious beings make. So maybe there is a contradiction.

[BananaStand]

When you realise that in order to measure the velocity and trajectory of a partcle, or even a large physical object such as the moon, one needs to at the very least fire photons at it

What?

Who's firing photons? We're just watching particles go through two slits, in two different ways, based upon which way the camera is pointing.

When you look at the moon, you aren't firing photons at it. It's the opposite. Your eyes are detecting photons that are coming from the moon.

[OngBonga]

Your eyes are detecting photons that are coming from the moon.

Sure, but some of those photons hit you and deflect back to the moon. Some photons that didn't originate from the moon and wouldn't have gone there if you hadn't looked at it are now deflected in that direction. By looking at the moon, you're changing the initial conditions that existed before you looked at the moon. Just changing your posture changes your gravitational relationship with the moon. In fact standing perfectly still won't help, even if you could, because the moon is moving, so is the earth, so your gravitational relationship with the moon is constantly changing.

Observation is interaction, and interaction changes the initial conditions.

[MadMojoMonkey]

I don't know dude. That all really sounds like a lot of maybes and excuses.

Still sounds to me like doing the exact same experiment will yield two different results based on whether or not certain parts of that experiment are being observed.

That's spooky fucking shit!

This is mostly spot on, actually.

I mean,there are no maybes* or excuses, but it does sound like I'm making stuff up.
Like I said: There's no reason you should believe hearsay on the internet, whether from me or colonel Sanders in spandex.

It is spooky. There are more spooky aspects to quantum, too.
Check out the EPR paradox.


*OK, saying that the position and momentum of all the things are actually best described by squaring a complex-valued probability density function, then integrating that over some domain - that sounds dangerously close to maybes... but it's really not. That probability density function is well-defined and repeated experiments continue to confirm its utility.

[BananaStand]

This is mostly spot on, actually.

I know. What about the subsequent post where we determine that I'm God? You on board with that too?

I mean,there are no maybes* or excuses, but it does sound like I'm making stuff up..

For what it's worth, it was better than Ong's explanation where photons shoot out of your eyeballs.

Like I said: There's no reason you should believe hearsay on the internet, whether from me or colonel Sanders in spandex

Let's be clear on one thing. This is the last time you badmouth the colonel.

It is spooky. There are more spooky aspects to quantum, too.
Check out the EPR paradox.

No shit it's spooky. So fuck your EPR paradox. I'm not interested in giving myself nightmares.

*OK, saying that the position and momentum of all the things are actually best described by [nerd talk]

I can sorta wrap my head around the idea of things being two places at once and all that. Like the electron passing through the double slit is both a particle and a wave. And it goes through both slits, and neither. Or just one. Or just the other. All at the same time. Fine.

What's not clear to me is how I can personally determine whether it's one thing or another just by my conscious decision to pay attention to it or not.

The idea that a thought is a physical thing that interacts with the environment around it is a pretty incredible thing to think about. Imagine the power that might be unleashed if a whole bunch of people all had the same thought at the same time!

[OngBonga]

For what it's worth, it was better than Ong's explanation where photons shoot out of your eyeballs.

lol shooting photons out my eyeballs.

I would hope a physicist can explain phsyics better than me.

[OngBonga]

And it goes through both slits, and neither. Or just one. Or just the other. All at the same time. Fine.

Pilot wave theory says the wave goes through both slits, but the particle only goes through one, following a trajectory based on initial conditions (which determines the wave's propogation). Because we can't measure the initial conditions without changing them (uncertainty principle), we observe apparent randomness that correlates with interference, but the randomness only emerges because we can't measure the initial conditions accurately. If we could, we'd know where the particle would land.

I'm not saying this theory is correct because I obviously have no idea, but it makes more sense than the Copenhagen interpretation, which is basically what you're talking about here with one particle going through two slits until observed, or whatever fucking nonsense they're spouting.

[BananaStand]

Thetans maybe?

[OngBonga]

Steady on with the thetans talk. This is the phsyics thread, not the monkey retard thread.

[MadMojoMonkey]

I guess I more meant that the effects of applied torque can be unintuitive, not the force itself. Hm so in car specs, torque is the rotational force applied to the crankshaft, and horsepower is the amount of work, or transfer of energy, the engine can do in a set time?

You gotta be careful with what the torque is referring to. The torque going into the transmission is not, in general, the same as the torque coming out of the transmission. A differential is a kind of gearbox, too, so it also changes torque from its input to output shafts, in general.

Torque coming out of the engine is not generally the same as torque coming out of the transmission, which is not generally the same as the torque applied to the wheels.

The power delivered in all cases is (nearly) the same, because of conservation of energy (but not exactly the same, 'cause friction and stuff).
Your definition of work is spot on.

Since energy is conserved in every split second, power is conserved, too. So the power into the transmission is roughly equal to the power coming out of the transmission.
Roughly equal because friction losses mean that the output of the transmission really includes heat and noise and other forms of dissipating energy.
This is true for all gearboxes.

A slowly spinning shaft with a high rotational force can be put through a gearbox to produce a faster spinning shaft capable of delivering less rotational force.
Also, the opposite is true. Gears are efficient tools for trading rotational force for rotational speed and back.

So the horsepower rating of the engine tells you how much constant brute force the engine is capable of producing.
The torque is a variable thing, depending on where you measure it.

[MadMojoMonkey]

Disclaimer: when talking about stellar evolution, physicists tend to talk about the core of the star. We go on about core collapse, and the effects thereof. This may clash with what you've heard about the sun's size expanding over the coming billion years to be larger than the orbit of Earth. The outer layers of a star expand as it ages, but the core collapses and becomes more dense as more "heavy" elements are fused.

It's something to bear in mind.

Also, I spent days creating this post, and I'm not sure where it's too heady and long-winded and where it's hard to follow and obtuse at this point.
Please follow up as needed.

***
lol... "Post Quick Reply" couldn't be less true.

Alrighty then, not as simple as I expected, not surprisingly. In the visualizations it's always stressed how far the electrons actually are from the nucleus and how much empty space there is in between.

Atoms are crazy little things [citation needed].

Just so that you don't think I'm saying that it's common for an electron to be inside a nucleus:
It is the case that electrons spend some time in the nucleus... that is... there is a non-0 chance of occasionally detecting an electron inside a nucleus.
It's not a very probable situation, but it is definitely part of the description of atoms.
The most probable place to find an atomic electron is definitely outside a nucleus.
A nucleus is generally ~(10)^-15 m in diameter.
An atomic diameter is generally ~(10)^-10 m.
So the atom (rather, its electron cloud) is 10,000 times as wide as its nucleus.

Like I mentioned before, the (10)^-15 m is misleading. It represents some probability of finding a nucleon inside that diameter. Just as electrons are sometimes inside of nuclei, nucleons are sometimes outside this nuclear size (it's ridiculously more rare, though). The forces acting on nucleons to hold them together are different than gravitational or electromagnetic forces, and nuclei therefore have a "hard shell." Meaning that finding a nucleon much beyond its parent nucleus means that it is no longer a part of that nucleus. I.e. you didn't find one of "that" atom's nucleons outside it's nucleus, you found a free nucleon, not bound to any nucleus.

If matter is mostly nothing, it just led me to think what would happen if you squeeze matter enough, and just picturing applying enough force to pack all of the atoms (or nuclei) together, with no empty space in between. I do realize it's not like electrons are just there spinning on perfect orbits around the nucleus like earth around the sun, but they're all over the place, even at the same time. That would have just been such a satisfactory intuitive explanation. So what does exactly happen when the force applied is nearing the Chandrasekhar limit, is the distance between the electrons and the nuclei being limited or how do they end up butting heads?

Keep in mind that what we're talking about now is not atoms, but plasma. Plasma is not made of atoms, per se.
An atom is some number of electrons bound to a nucleus with the same number of protons and any number of neutrons. If protons and electrons are not in equal numbers, it is not an atom, strictly speaking, but an ion.
Plasma consists of fully ionized nuclei (the nuclei have no electrons bound to them) going crazy, mad bonkers in a sea of electrons, also going crazy, mad bonkers.

The plasma forms from pre-stellar atoms when the thermal energy (created by increasing pressure due to gravitational collapse) overcomes the electron binding energy. In any collision (particle interaction), now, the average thermal energy delivers more energy to the electron (or nucleus, doesn't matter) than the energy binding it to the atom, and so the nucleus / electron(s) become(s) unbound.

Now what we have is a bunch of nucleons bound gravitationally and a bunch of electrons bound gravitationally. These 2 clouds are also coupled to each other. Each cloud acts to disperse itself, being composed entirely of like charges. However, the clouds are of opposite charge to each other, which means they attract each other. The net effect is that the 2 clouds remain interspersed through each other, shielding each other from the extreme dispersing forces of like-charge repulsion.

So what we have is a state of plasma. The core of collapsing star is basically a single quantum object, composed of unfathomably many entangled particles. We're talking about electron degeneracy pressure, so let's ignore the nucleons for a minute. Remember before when the thermal energy went past some threshold, it turned the atoms of the proto-star in to a plasma. This change happened because it was energetically favorable for the electrons to be unbound from their nuclei. I.e. it would have taken MORE energy to hold the atoms together than it did to create the plasma.

A similar thing is going to happen with the creation of a white dwarf star. The core of the star started to fuse Iron, which is always the end of that star. Iron fusion is endothermic, not exothermic. The outward pressure holding off the full gravitational collapse of the star is due to exothermic fusion reactions of elements lighter than Iron. Those exothermic reactions provide an outward force to balance the gravitational force. With Iron, the reaction not only doesn't provide any outward force, it contributes to the inward pull. For all stars, Iron fusion means supernova is imminent. (The iron in your blood was literally made by the death of a star.)

What I'm describing is a runaway reaction in which the pressure in the core of the star is increasing as the volume (of the core) decreases. That volume contains a mostly constant number of electrons. (There are nuclear decays going on which cause it to fluctuate, but it's fairly constant.)

Now it's gonna get ugly. There's no way to summarize what's going on any better than you understand without getting into quantized wave mechanics.
OK, oscillators.
If I have 2 masses, connected by springs, then they can move in 2 basic ways. Either they move together as a unit, where the spring does nothing, or they bounce back and forth, always moving in opposite directions to each other in the center of mass rest frame. No matter what movement you see them exhibit, it is always some additive combination of those 2 states.
If I have 3 masses, connected by springs, then they can move in 3 basic ways. As always, they can move together as one unit, where the springs do nothing. This is always the lowest energy state. They have an intermediate state, where the 2 "outer" masses move in opposite directions of each other, but the "middle" one sits still. The highest energy state is always one in which every mass is moving in the opposite direction as its adjacent neighbors.
With quantized systems, here, the number of masses is quantized, there is always a highest energy state... A maximum amount of energy that can be (nearly losslessly) stored in that system.

OK, it's well different with electron states, and we're talking about the state of a ridiculous number of particles in an ensemble, but the fact that there is a maximum energy that can be stored in the system still holds. As the volume decreases, the number of available states decreases. When the number of available states is equal to the number of fermions (particles that don't share states) in those states, then extreme physics is going on.

The increasing pressure can no longer compress the core of the star, because the core is effectively incompressable under the applied pressure. It can't reduce its volume with that number of electrons in there, and the electrons have nowhere to go. It will take a LOT more energy to make it energetically favorable for the electrons to undergo a process called electron capture. In electron capture, a proton and an electron interact, and a neutron and electron neutrino are left.

In fact, no free proton has ever been witnessed to spontaneously decay. Free neutrons do spontaneously decay into a proton, electron and anti-electron neutrino. This is because the combined rest-mass (energy) of the resulting particles is less than the rest mass of the neutron (and other conservation laws are followed).

In general, for small atoms, the lowest energy state for the nucleus is to have an equal number of protons and neutrons. As we look at larger atoms, we see more and more neutrons than protons. This is because protons have the same sign of electric charge and they're stupid close together. The repulsive forces they express on each other are stupendous. So protons in a nucleus have more energy than neutrons in the nucleus, because they experience a force that the neutrons (not having electric charge) do not.

Nonetheless, if you put a few neutrons together in a nucleus with no protons, at least one of them kinda immediately decays into a proton, because neutrons have the same wave mechanics constricting them in a specific volume as we talked about before. (protons, too). So if you got a bunch of neutrons, and no protons, then it's definitely lower in energy to take one of the highest energy neutrons in that volume and move it to the lowest energy available proton spot. That doesn't even count the bonus energy of a spontaneous decay.

The practical upshot is that in order to compress the electron degenerate matter to neutron degenerate matter, there is a steep cost in energy to pay. Those neutrons are higher in energy than protons, and still confined to a finite volume. If the infalling matter of the collapsing stellar core is does not create enough pressure to pay this cost, then it basically hits an immovable wall and rebounds in a supernova.

The same rebound happens when it collapses to a neutron star, and the neutron degeneracy pressure cannot be overcome.

When the neutron degeneracy pressure is overcome, it collapses into a black hole (or some theorized objects, not yet observed).

[MadMojoMonkey]

observed = measured

In this context, yes.

The act of measuring changes the initial conditions. Of course there will yield two different results based on whether or not it was observed. That's not spooky, it's totally intuitive. How do you "meausre" the velocity and location of a particle? Or, more to the point, how do you do this accurately without altering its trajectory and thus changing the conditions? Hint - you can't, see "uncertainty prinicple".

This is measurement uncertainty and it is a separate problem than quantum uncertainty laid out in the uncertainty principle.

Measurement uncertainty is a common problem. Consider measuring your car's tire's pressure. By attaching the pressure gauge to the tire, you obtain a reading by releasing some of the pressure into the tire pressure gauge. You cannot measure the pressure with that gauge without altering the pressure you're trying to measure.

This applies to quantum particles, too, but it is NOT the uncertainty principle.

The uncertainty principle says that, even with "perfect" measurement devices, you still cannot simultaneously measure the position and momentum of something to arbitrarily high precision. Those properties DON'T SIMULTANEOUSLY EXIST IN THE UNIVERSE for any particle... because particles are waves, and waves have this property.

The double slit experiment can be explained by pilot wave theory. I'm not sure what to make of it all, but the basic gist is every particle has an associated wave, and the wave essentially carves out a geomoetric path for the particle to follow. The trajectory of the particle is determined by its initial conditions, at least until we try to measure it, thus changing its trajectory.

That pilot wave is the imaginary portion to the solutions of Schroedinger's Wave Equation. Particle wave functions are complex-valued. To determine probabilities of observing certain properties of a particle, you square the wave function and integrate over some domain. The squaring eliminates all negative and complex values from the result, making them neatly measurable predictions.

There is no known way to measure a complex-valued wave, and the pilot wave theory is predicated on these imaginary solutions directing the particles' apparently random motions in deterministic ways. It's a comfortable view, but not falsifiable by any known means, so not, strictly speaking, science.

[OngBonga]

The uncertainty principle says that, even with "perfect" measurement devices, you still cannot simultaneously measure the position and momentum of something to arbitrarily high precision.

hmmm I kinda saw the "uncertainy principle" as the quantum version of the tyre pressure thing, that it was basically impossible to obtain a perfect measurement because to measure velocity perfectly changes the location, and vice versa. Clearly not.

It's a comfortable view, but not falsifiable by any known means, so not, strictly speaking, science.

I thought this theory got revived in the 50's? Is De Broglie–Bohm theory not science in the strictest use of the word?

[Poopadoop]

Why does a spinning object fly straighter than a non-spinning object?

[MadMojoMonkey]

I thought this theory got revived in the 50's? Is De Broglie–Bohm theory not science in the strictest use of the word?

If you can find a way to measure the pilot wave and show that it is a physical thing, and that particles follow deterministic trajectories, in compliance with the forces of the pilot wave, then Nobel Prize for you, sir.

Note: I am not authorized to hand out Nobel Prizes.

[MadMojoMonkey]

Why does a spinning object fly straighter than a non-spinning object?

Conservation of angular momentum.

In an isolated system, the angular momentum of the system is a constant.

[Poopadoop]

Conservation of angular momentum.

In an isolated system, the angular momentum of the system is a constant.

Uh, yeah.

Now how about in English?

[OngBonga]

If you can find a way to measure the pilot wave and show that it is a physical thing, and that particles follow deterministic trajectories, in compliance with the forces of the pilot wave, then Nobel Prize for you, sir.

I'm on it.

[MadMojoMonkey]

Uh, yeah.

Now how about in English?

Sorry.

***
"In an isolated system,"
I'm talking about a spinning thing (or group of things) that is not being torqued or pushed by anything

"the angular momentum of the system"
The total amount of spinning-ness of the thing

"remains constant"
does not change.

***
For clarity of nomenclature, spinning things don't fly straighter than non-spinning things, they maintain stability while flying just as straight as an unstable thing.
(or I've misunderstood your question.)

It's the rotational equivalent to Netwon's First Law
"In an inertial reference frame, an object in motion will remain in motion at a constant velocity if and only if the vector sum of forces acting on the object is 0 N."
(Note that 0 is a 0 vector, for the math nerds who care about that stuff.)

In other words:
Stuff changes how it moves only when it's pushed, but pushes which cancel each other out don't change how objects move.
Therefore, we can deduce if something has been pushed by seeing if it changes how it's moving. If it changes, it was pushed.

A nearly identical rule holds for spinning things. If they change, then they must have been pushed. If nothing is pushing (or all pushes are cancelling out), then it will not change.

Spinning things have a non-0 rate of angular momentum (actively spinning inertial mass). Since it is spinning, it will not change without a push... but now I have to clarify that a spinning push is a torque. So spinning things only change their spinning if they are torqued.

Spinning things have an axis of rotation, which partly defines their spinning. If the orientation of that axis of rotation changes, that requires a torque to have changed it. In general, the friction on a spinning object is such that it slows the spinning w/o changing the orientation of the spinning axis.

So, like, a frisby maintains stability because it is spinning and that spinning has an axis of rotation. In order to change the axis of rotation, a torque must be applied to the frisby. However, the air resistance acting on the frisby supplying a torque is generally pretty balanced around the edge of the frisby, putting roughly equal forces of friction all around the frisby. These tend to slow the rotation w/o changing the orientation of the rotation.

It occurs to me that a frisby always rolls over to one side and that since it is moving forward as it spins, the air velocity across the advancing edge of the frisby will not be the same as the friction along the retreating edge. This could cause a net torque which serves to drive the roll-over of the frisby.

[OngBonga]

Uh, yeah.

Now how about in English?

I'll give it a bash.

Take the earth-moon system, and simplify it to say that the moon is moving perpendicular to earth, while earth's gravity acts to draw the moon towards earth. If the moon was not moving perpendicular to earth, it would fall directly towards earth. But because it has linear velocity, then it moves in a circle around earth (I emphasise, very simplified).

That's conservation of energy.

Conservation of angular momentum is basically the same, only applied to a rotating frame of reference. If you imagine a spinning top, if you give it a push to try and make it fall over, it won't, because the part you made fall towards the direction of gravity has moved and is now going against gravity, before reacing its apex and going back down with gravity, etc.

Conservation of angular momentum is basically conservation of energy, just more complex because of the nature of motion.

[CoccoBill]

I think poop is asking why guns have rifling.

[Poopadoop]

That, or why you spin a ball when you throw it.

A spinning object doesn't fly straighter than a non-spinning object? Then what is the point of making it spin - what is rifling for, for instance?

I thought if the thing wasn't spinning, it was free to rotate in all kinds of weird ways (e.g., a bullet flying end-over-end) which could cause the wind resistance to make it deviate from a straight path. I just didn't understand how the spin kept it straight.

Isn't the whole idea of a knuckleball to remove the spin from the ball so it will move in unpredictable ways?


So ya, my question is why does imparting a spin to an object keep it from tumbling around in the air?

[MadMojoMonkey]

A spinning object doesn't fly straighter than a non-spinning object? Then what is the point of making it spin - what is rifling for, for instance?

I thought if the thing wasn't spinning, it was free to rotate in all kinds of weird ways (e.g., a bullet flying end-over-end) which could cause the wind resistance to make it deviate from a straight path. I just didn't understand how the spin kept it straight.

Sorry if I've been confusing. This is exactly what I mean.
(You've also touched on the answer to your question. more in a bit)

In an inertial reference frame, accelerations are caused by forces, not by spinning.

The spinning doesn't make it fly straight, it makes it less susceptible to tumbling.
This makes is less effected by the forces of wind resistance.
The reduced effect of wind resistance makes it fly straight by reducing random accelerations from causing it to deviate from its trajectory.

Take away the air, and the air resistance which exerts forces on those objects goes away, and the spinning doesn't matter.
Things fly straight, spinning or not.
(Well, in a gravitational field, they follow trajectories, which are not "straight" outside of invoking GR.)

That, or why you spin a ball when you throw it.
[...]
Isn't the whole idea of a knuckleball to remove the spin from the ball so it will move in unpredictable ways?

So ya, my question is why does imparting a spin to an object keep it from tumbling around in the air?

Yes.

Imparting a spin means that any "small" torques which are exerted by wind resistance will have a less dramatic effect on the direction the thing is rotating. Since it's spinning "really fast" about an axis, any "small" torques which are exerted on it will "probably" not change its direction of rotation "very much." Just like if something is moving "really fast" in a straight line, any "small" random forces will cause it to deviate, but it's "probably" still "generally" moving in the same direction it was.

[OngBonga]

(Well, in a gravitational field, they follow trajectories, which are not "straight" outside of invoking GR.)

Fuck you, invoke GR. It's a straight line.

[MadMojoMonkey]

Fuck you, invoke GR. It's a straight line.

I was thinking of you when I typed that.

While technically you are correct, it doesn't make this explanation any simpler.

[MadMojoMonkey]

hmmm I kinda saw the "uncertainy principle" as the quantum version of the tyre pressure thing, that it was basically impossible to obtain a perfect measurement because to measure velocity perfectly changes the location, and vice versa. Clearly not.



I thought this theory got revived in the 50's? Is De Broglie–Bohm theory not science in the strictest use of the word?

All known attempts to make a comfortable, intuitive, sensible explanation of QM have either been terribly flawed in inconsistencies or have failed at their goal.
The 3 most popular interpretations are as follows:

As we've discussed briefly, the pilot wave hypothesis relies on these imaginary forces that make deterministic processes appear random.

The many worlds interpretation cannot be falsified, either. That's the idea that all possible quantum states exist simultaneously, and our universe represents one particular probability slice of that poly-verse.
(Any Hitchhiker's Guide fans, here? The "Whole Sort of General Mish Mash" bit always comes to mind when I think of the many worlds theory.)
Anyway, since we can only observe our own universe, by definition... our universe is everything we can observe and all that is directly implied we could observe if we had been in the right place at the right time. There is no way to measure these other universes' outcomes.

I tend to preach the Copenhagen interpretation like it's gospel, but it's equally messed up in the assertions. A few posts back, I explained Young's double-slit experiment as the evolution of a wave which exists in a superposition of states, and even when a particle doesn't get detected by a detector, the wave function still interacted and collapsed, leaving the rest of the wave function to continue.
So I asserted that a lack of detection (or any measurable event, for that matter) still caused a measurable change in the universe - the pattern on the wall behind the undetected hole still looks like the pattern behind the detected hole, so long as the detector is on.

That assertion relies on unmeasurable events being causes, in much the same way that I criticize the pilot wave interpretation.
:/
Frankly, I should look at the pilot wave interpretation a bit more closely. I like Copenhagen because it relies on the math, which is experimentally confirmed. On the surface, that's also true of pilot wave, so ... cool.

[MadMojoMonkey]

Thanks for this analysis, I'll get back to you when the weather perks up again and I put this into action!

Keep in mind that you don't want that evaporated water in the room. It bears the energy and keeping that energy out is kinda the point.

It's important that the water is evaporated by energy taken from the room. Adding an energy source to evaporate the water kinda eliminates the point.

Keep me posted. You'll want a cool room while you setup your pilot wave detector.

[MadMojoMonkey]

So I can change the temperature outside by walking outdoors with a thermometer?

Theoretically, yes... ish.
Your presence is definitely emitting ~75 Watts of heat when you're inactive. It can be as high as ~150 Watts under intense physical exertion, like any time your breathing is elevated for a sustained period.
This is going to trump the small amount of heat being absorbed or emitted by the thermometer as it comes into thermodynamic equilibrium.

Being able to measure and prove the heat a body emits in a well insulated room of any size is standard. In laboratories where temperature control is essential, there is generally a line of 100 W lamps in the room and whenever a researcher enters the lab, they turn off a light, and turn it back on when they leave. This helps maintain the heat being generated in the lab.

Proving this happens in the atmosphere with a thermometer is going to be impossible.

Conservation of Energy still holds that if you're emitting heat into the atmosphere, then the atmosphere is getting warmer. Whether or not you're inside is probably of minimal relevance. The air in your house is cycled with outside air more often than you may think, but it varies widely. It's just that the atmosphere is really big [citation needed] and the cumulative effect your body heat has on global climate is negligible.

Sorry, I'm not buying it.

There goes my retirement!

The fact that I can change the behavior of matter in a way that defies is explained by the rules of physics, merely by exercising my own consciousness, pretty much proves that I am God.

Or at least, a god

FYP, oh mighty god-brother.

[OngBonga]

The many worlds interpretation cannot be falsified, either.

I still haven't thrown a cup of boiling tea in my face.

That assertion relies on unmeasurable events being causes, in much the same way that I criticize the pilot wave interpretation.

From what I could tell, there wasn't much between Copenhagen and pilot wave. The difference seems to me that one is an outcome determined by probability, while the other is an outcome determined by initial conditions. The latter seems much more intuitive to me.

I really, really do not like the idea that everything we observe is a roll of the dice. I don't like randomness in nature. It don't believe randomness exists in nature, just apparent randomness that needs better understanding. But this opinion is much more philosophical than scientific. This is why I like pilot wave (or whatever it evolved into), it removes that aspect from QM. That's not to say I understand pilot wave, because I don't, but I like it.

[OngBonga]

It's important that the water is evaporated by energy taken from the room. Adding an energy source to evaporate the water kinda eliminates the point.

The water would be evaporated by the excess heat in the room. The question would be how to remove the water from the air without putting heat back into the room. A dehumidifier will condense water, so that releases the energy back into the room. I suppose I could vent the air out of the room onto the landing, where I can run the dehumidifier. That takes the heat into another room, which has better ventilation.

[OngBonga]

I had a suggestion from a friend... put a plant next to the computer. Evapotranspiration will cool the immediate surroundings, and if I can keep on top of humidity, then this process will be maximised. This might be more pleasing to the eye than having trays of water lying around.

[MadMojoMonkey]

What about making a heat exchanger?

Set up a freezer in the landing. (or wherever, so long as it's radiator is outside the room).
Wind some copper tubing into a coil and make sure a fan is blowing across the coil.
Attach a flexible, insulated tubing like surgical tubing to the ends of the coil and run those ends out of the room.
Attach another bit of copper tubing to the ends of the flexible tubing and set that in the freezer
Add some water & anti-freeze to the tubing as your working fluid.

A pump may or may not be necessary. If the coil and fan in the room is lower in elevation than the freezer, convection will drive a flow. Probably convection wont be enough, so a pump is likely to be necessary.

The freezer can be replaced with a cooler full of ice, but the freezer requires less maintenance.

[OngBonga]

Hmm interesting. I'll try plants first, I like that idea because it's easy maintenance plus it looks nice, also minimal setting up. If that doesn't help matters, I'll look at this little setup. Sounds like it could be fun. Cheers.

[Poopadoop]

Hmm interesting. I'll try plants first, I like that idea because it's easy maintenance plus it looks nice, also minimal setting up. If that doesn't help matters, I'll look at this little setup. Sounds like it could be fun. Cheers.

Why don't you just buy a bag of ice (or make some in the freezer), put it between you and a fan, and blow the fan over the ice?

[Savy]

Ong are you mad, just buy a water cooling system for your pc, they aren't exactly expensive and they'll actually work as opposed to a plant.

[BananaStand]

Do they not have air conditioners in the UK?

[Savy]

Do they not have air conditioners in the UK?

Not in homes, why would we need it?

[BananaStand]

Not in homes, why would we need it?

To condition air

[Savy]

To condition air

Clearly you've never been to the UK.

[BananaStand]

Clearly you've never been to the UK.

Clearly.

And I don't see it as a bad thing either. It doesn't seem like a nice place. Every time I see pictures, it's raining. Everyone's teeth are fucked up. Your government has elections whenever it wants. And I have to say, a woman with a british accent is probably the least sexy thing on earth. It's a tragedy when the woman is actually attractive. It's like being served your favorite meal, but then the waiter spray-farts on it.

Anyway......none of that explains why you don't have air conditioners. You have windows, you have electricity. All you need now is 90 bucks to buy the AC unit and it's your world.

[MadMojoMonkey]

Keep it on topic, lads. This is the physics thread.

[Savy]

Clearly.

And I don't see it as a bad thing either. It doesn't seem like a nice place. Every time I see pictures, it's raining. Everyone's teeth are fucked up. Your government has elections whenever it wants. And I have to say, a woman with a british accent is probably the least sexy thing on earth. It's a tragedy when the woman is actually attractive. It's like being served your favorite meal, but then the waiter spray-farts on it.

Anyway......none of that explains why you don't have air conditioners. You have windows, you have electricity. All you need now is 90 bucks to buy the AC unit and it's your world.

8/10 effort, 1/10 effectiveness

D

[OngBonga]

Why don't you just buy a bag of ice (or make some in the freezer), put it between you and a fan, and blow the fan over the ice?

Problem is that I'd need to keep doing it. How long does a bag of ice last in a room that's 35 degrees?

Ong are you mad, just buy a water cooling system for your pc, they aren't exactly expensive and they'll actually work as opposed to a plant.

My PC is probably worth a fiver, so not sure if worth it. Still, I'll look into this, certainly when I replace this heap of shit.

Plants should work. Evapotranspiration is a thing that plants do, and it cools air around the plant.

Do they not have air conditioners in the UK?

They're not cheap, and for the most part, we don't need them. We probably have a max of 5 days a year where it's +30 degrees outside.

[BananaStand]

Keep it on topic, lads. This is the physics thread.

Ok, please confirm my understanding of physics here.

You feel hot because it's summer time. You go to the store, pick out an AC unit, give the guy at the register 90 bucks, and then go home. You put the unit in your window, close the window on top of it, and plug it in. Then you hit the switch and you live in climate controlled bliss until winter.

Is that how it works?

Now, what kinda silly physical anomalies are preventing that same thing from happening in jolly ol' england?

[OngBonga]

Now, what kinda silly physical anomalies are preventing that same thing from happening in jolly ol' england?

Something called cost/benefit ratio. It's not just 90 bucks, you've also got to run the thing, which costs x amount on your monthly outgoings. Furthermore, when it's being used 5 days a year, one has to question if it's just better to suck it up on the few hot days we have.

[BananaStand]

Something called cost/benefit ratio. It's not just 90 bucks, you've also got to run the thing, which costs x amount on your monthly outgoings.

Great, now weight that against the cost of getting a new computer. Or consider the cost to your relationships when your friends come over and see you running a fan over trays of ice so you can maintain the toy you use for internet rants and porn.

90 bucks seems like a steal.

[OngBonga]

I'm sure I said somewhere that my comp room has no windows. Where the AC unit going?

Great, now weight that against the cost of getting a new computer.

That's gonna happen this year anyway.

Or consider the cost to your relationships when your friends come over and see you running a fan over trays of ice so you can maintain the toy you use for internet rants and porn.

I'm going with houseplants first, remember? I don't think my friends will find anything unusual about that. Even so, I'm not in any hurry to invite guests into my warm humid comp room with one seat so we can watch porn together.

[OngBonga]

Anyway, let's take this convo to another thread.

[OngBonga]

Back to physics...

http://www.bbc.co.uk/news/science-environment-39642992

What the actual fuck is negative mass? I've come to understand mass as resistance to acceleration. The "heavier" something is, the more resistance it has. Something with zero mass, ie a photon, has no mass because it has no resistance to acceleration... it always moves at c, so does not experience a change in state of motion, thus, no mass.

So how can negative mass be explained in inertial terms?

[BananaStand]

Back to physics...

http://www.bbc.co.uk/news/science-environment-39642992

Am I understanding this correction if I'm envisioning this discovery leading to the development of tractor beams?

[OngBonga]

Am I understanding this correction if I'm envisioning this discovery leading to the development of tractor beams?

I'm not understanding it at all right now. I'm hoping mojo can explain this in inertial terms so I can get my head around it.

[BananaStand]

I'm not understanding it at all right now. I'm hoping mojo can explain this in inertial terms so I can get my head around it.

I'm kind of focusing in on the part where if you push an atom, it moves toward you. And I'm envisioning US satellites firing something at North Korean missiles that makes them fly upwards and off into space.

[OngBonga]

I'm kind of focusing in on the part where if you push an atom, it moves toward you. And I'm envisioning US satellites firing something at North Korean missiles that makes them fly upwards and off into space.

Obviously this is speculation because I have no fucking idea what we're even talking about, but I'm assuming that the amount of force required to propel something is the same... just in the opposite direction. So I'm not sure it has potential applications when it comes to propulsion.

For argument's sake, let's say it takes 100 of energy to propel something into orbit, with the force applied underneath the object. Well, we still need 100 energy, we just apply the force to the top instead.

However, the term "fuck knows" keeps popping into my head.