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/sci/ - Science & Math

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File: 475 KB, 400x580, ElementalHEROAbsoluteZero-GENF-EN-SR-LE.png [View same] [iqdb] [saucenao] [google]
6502622 No.6502622 [Reply] [Original]

Why is there a limit on how cold things can be but not how hot they can be?

>> No.6502623

>>6502622

There is a limit. Eventually it get too hot for anything to exist. So there is nothing to get hotter.

>> No.6502629

>>6502622
There is, google it.

>> No.6502632

>>6502622
0 K is just the absence of heat energy. The hottest anything has ever been would be the moment of the big bang, where all the energy of the universe was compressed. That gives a finite limit to the amount of heat possible.

No energy < current heat < all energy

>> No.6502633

>>6502623
have we discovered that magic number?
whats the currents highest space temperature

>> No.6502642

>>6502622
well seeing as absolute zero is when particles have no kinetic energy maximum temperature would be when they have maximum kinetic energy ie their velocity is equal to the speed of light.

>> No.6502648

Sometimes you get so hot your temperature becomes negative

https://en.wikipedia.org/wiki/Negative_temperature

>> No.6502650

>>6502642
It takes infinite energy to move a particle with mass with the actual speed of light.

>> No.6502653

>>6502650
so are photon and neutrinos negative mass?

>> No.6502654

>>6502633
It's a contentious issue. Or at least it was in '08.
http://www.pbs.org/wgbh/nova/physics/absolute-hot.html

>> No.6502656

>>6502648
Sometimes, you get so cold, it becomes hot.

https://en.wikipedia.org/wiki/Hypothermia

>> No.6502660

>>6502653
They have no mass.

For massless particles, e = pc, where p is momentum and c is the speed of light. This is conforming to the full relativity equation where you set mass m to 0.

e^2 = (mc^2)^2 + (pc)^2

>> No.6502661

>>6502648
So temperature is like a signed n-bit integer? If you add one to its max positive value it becomes negative.

>> No.6502676

For an ideal gas,

<span class="math">\frac{1}{2}mv^2 = \frac{3}{2}\frac{A_N}/RT[/spoiler]

Where m is the mass of the gas, v is the root mean square of its velocity, <span class="math">A_N[/spoiler] is Avogadro's constant, R is the ideal gas constant, and T is its temperature. Obviously, v=c is the maximum temperature for that gas.

>> No.6502677

>>6502676
Well i fucked it up.

Right side should be (3/2)*(A/R)*T

>> No.6502683

>>6502676
im so happy that you noted its only for an ideal gas i could cry.

>> No.6502684

>>6502661
almost, except that you need to go to infinity before jumping to -infinity.

temperature is a shit quantity, inverse temperature is the real thing, and inverse temp can be positive, negative or 0, but 1/positive is positive and 1/negative is negative with 1/0 the place where you jump from positive infinity to negative infinity.

>> No.6502685

>>6502648
https://www.youtube.com/watch?v=yTeBUpR17Rw

>> No.6502689

Vsause did a video on this exact topic.

https://www.youtube.com/watch?v=4fuHzC9aTik

>> No.6502703

>>6502660
Actually neutrino has mass

>> No.6502704

>>6502622
Because temperature is the (approximate) measure of the absolute magnitude of various deviations.

>> No.6502708

>>6502703
A neutrino travels at between 0.999976c and c. That's experimental data from the 2007 MINOS detector measurements.

>> No.6502711

>>6502708
neutrino oscillation require a nonzero mass.

theoretical prediction >> experimental data

>> No.6502712

>>6502711
1. Neutrinos have a nonzero mass
2. Neutrinos are slower than the speed of light
These facts are not contradictory.

>> No.6502738

Because negativity does not exist and is a construct of the human mind.

Negative numbers fulfill the same role as complex numbers

>> No.6502888

>>6502684
>temperature is a shit quantity, inverse temperature is the real thing
Replace 'inverse temperature' with 'entropy' and I'll be very inclined to agree.
Incidentally, of the five fundamental Planck units, temperature is the only one that's 'large'. All the others (length, time, charge, mass) are 'small'. I don't know if there;s a meaningful physical interpretation for the reciprocal Planck temperature, but I wouldn't be surprised to find one.

>> No.6502912

>>6502888
inverse temperature is the relationship between entropy and energy, you cant replace it with entropy. and in plank units the temperatures equal to energy, so its because the plank energy is so large.

>> No.6504424
File: 759 KB, 976x4421, temperature.png [View same] [iqdb] [saucenao] [google]
6504424

>>6502622
It depends on how you model things, as we don't really know that much.
I mean this whole deal with negatives temperatures being hot could just be an error from an incomplete mathematical model.

I have the crazy idea to draw the line where energy densities should start forming matter and thus cool down as the energy is turned into matter, of course that just my unsubstantiated idea. I also wonder if the reverse is true, as it gets so cold matter breaks down heating things up. After all at such extremes I would guess the potential difference to do crazy things is there, but I need more nuclear physics to figure it out.

If you want something that is not my musings, then look up
http://en.wikipedia.org/wiki/Hagedorn_temperature
http://en.wikipedia.org/wiki/Absolute_hot

>> No.6504450

Because of what temperature is.
Eventually, temperature and matter are just energy.

0 temperature, speculatively, could simply mean zero matter.

>> No.6504797

>>6502912
>the plank energy is so large

It isn't, really. It's only about 543.3 kWh.

For comparison, the average household uses about 903 kWh per month.

>> No.6505018

>>6504797
and, thats not large to you?

stop talking out of your ass

>> No.6505080

>>6505018
The Planck energy is also about the same amount of energy that's in a car's tank of gas.