The Universe Could End In 2.8 Billion Years

[Tsumi]

So much hostility, you purpose built an argument to knock down without addressing the comment as a whole, and you put words in my mouth that I never said, then when caught you pull out a single sentence to justify your man, but fine fair enough.

A theory is a theory until disproved. Science is all about observation, leading to hypothesis, testing the hypothesis by attempting to make it fail, if the hypothesis stands up to enough testing (preponderance of evidence) then it can become a scientific theory.

Theories are not fool proof. We do not stop testing theories nor should we. A single failure will not likely discard the theory, such as Newtonian Physics utterly failing on a quantum level. To my knowledge we still cannot reconcile Newtonian to Quantum physics. Both theories could be wrong, but they are the best guess we have at how things work.

A Scientific Theory is not a Scientific Law.

What is a Scientific Theory?

Who's attacking who, and who's being hostile? You were the first to come out of the gate with accusations. A theory is not a hypothesis. In talking about science, a theory is a scientific theory, and the layman's definition of theory should not be used while discussing science.

It starts with a question or an observation, which leads to a hypothesis. It doesn't start with a theory, as you say it. Additionally, a hypothesis can be altered as more evidence comes to light. Same with scientific theories. Our scientific theories are at the point where it's not a question of whether they're wrong, it's a question of how complete they are. General relativity did not invalidate gravitational theory when it came out, it simply added to gravitational theory. The same will happen when scientists and mathematicians can find a way to unify general relativity and quantum physics. It will not invalidate either theory, it will add on to both theories. The theories aren't wrong, they're just incomplete.

 

[Epic|]

So much hostility, you purpose built an argument to knock down without addressing the comment as a whole, and you put words in my mouth that I never said, then when caught you pull out a single sentence to justify your man, but fine fair enough.

A theory is a theory until disproved. Science is all about observation, leading to hypothesis, testing the hypothesis by attempting to make it fail, if the hypothesis stands up to enough testing (preponderance of evidence) then it can become a scientific theory.

Theories are not fool proof. We do not stop testing theories nor should we. A single failure will not likely discard the theory, such as Newtonian Physics utterly failing on a quantum level. To my knowledge we still cannot reconcile Newtonian to Quantum physics. Both theories could be wrong, but they are the best guess we have at how things work.

A Scientific Theory is not a Scientific Law.

What is a Scientific Theory?

It's not Newtonian physics that must be reconciled with quantum mechanics but relativity and QM that must be reconciled with each other. They're both correct as far as we can verify but, as the poster before me states they seem incomplete given the discontinuity between them.

Newtonian physics is a specific, limited case of special relativity. Similarly we may find a new set of equations that bridge the gap between QM and relativity without invalidating them

 

[michalrz]

I've been kind of holding out from posting here but I'd like to ask a few questions about 'heat death'.

I hope some of you can point me in the right direction, I'm a layman as far as astrophysics and such go. So feel free to point out my mistakes. I know I'm probably mixing Newtonian, Quantum and Potato.

As a particle (say, a lone Hydrogen atom somewhere in the distant universe) cools down, its 'vibrations' weaken. Its electron drops to lower 'orbits'. Each of these drops causes energy to radiate away. All the way down to the ground state.
The proton retains its charge. Mass is still there. The electron doesn't disappear or collapse into its proton.
But the 'location' of its electron is still just probable. It has mass, so it still has gravity and it's basically the only way it interacts with the rest of the universe.
So, this atom does not undergo any change if untouched. And its gravity (albeit minute) still has infinite range.

Now, how the hell can we even find it then? Or even find out how many of them exist? Gravity cues? How would you know which atom is currently affecting you the most?
Now what? Do I whip out a flashlight and flood the universe with photons until I receive a reflection? And even if I did, I have just added some energy to that system, so all I have found out was: there was a Hydrogen atom somewhere. By the time the light returns to me, it could have moved or became something else. Better yet, how would I know that's the photon related to my experiment?

I'm sorry if this is all rubbish. I'm not a physics/math person.

 

[Tsumi]

I've been kind of holding out from posting here but I'd like to ask a few questions about 'heat death'.

I hope some of you can point me in the right direction, I'm a layman as far as astrophysics and such go. So feel free to point out my mistakes. I know I'm probably mixing Newtonian, Quantum and Potato.

As a particle (say, a lone Hydrogen atom somewhere in the distant universe) cools down, its 'vibrations' weaken. Its electron drops to lower 'orbits'. Each of these drops causes energy to radiate away. All the way down to the ground state.
The proton retains its charge. Mass is still there. The electron doesn't disappear or collapse into its proton.
But the 'location' of its electron is still just probable. It has mass, so it still has gravity and it's basically the only way it interacts with the rest of the universe.
So, this atom does not undergo any change if untouched. And its gravity (albeit minute) still has infinite range.

Now, how the hell can we even find it then? Or even find out how many of them exist? Gravity cues? How would you know which atom is currently affecting you the most?
Now what? Do I whip out a flashlight and flood the universe with photons until I receive a reflection? And even if I did, I have just added some energy to that system, so all I have found out was: there was a Hydrogen atom somewhere. By the time the light returns to me, it could have moved or became something else. Better yet, how would I know that's the photon related to my experiment?

I'm sorry if this is all rubbish. I'm not a physics/math person.

Correction: electron energy orbits are not the same thing as thermodynamic vibrations. Dropping electron energy levels gives off some form of radiation, while temperature is only dependent on how fast the molecule as a whole is vibrating.
We see things jn the universe by light given off from other objects (primarily stars, also often entire galaxies). We know how fast something is moving away from us by two things: the spectral signature of elements and redshift phenomenon. Each element gives off a unique wavelength pattern that is well known, and by spotting the pattern, seeing how much the redshift is, we can determine how quickly it's moving away and estimate approximately how far away it is.
Detecting objects by gravitational waves is something that was only accomplished recently by LIGO, and it detected the merging of two black holes. We cannot detect a single hydrogen atom, but we can detect clouds of hydrogen by the light they obscure.

 

[michalrz]

Correction: electron energy orbits are not the same thing as thermodynamic vibrations. Dropping electron energy levels gives off some form of radiation, while temperature is only dependent on how fast the molecule as a whole is vibrating.

Okay, I'm with you so far I think. Overall I was focused on objects which would be hypotethically cooled to true zero. I should have clarified that, sorry.
So, at 0 Kelvin (theory, I know), the electron does not necessarily have to be in its lowest state, yes?

We see things jn the universe by light given off from other objects (primarily stars, also often entire galaxies). We know how fast something is moving away from us by two things: the spectral signature of elements and redshift phenomenon. Each element gives off a unique wavelength pattern that is well known, and by spotting the pattern, seeing how much the redshift is, we can determine how quickly it's moving away and estimate approximately how far away it is.

Okay, I'm still here I think Okay so let's say something is moving away from us but it's at absolute zero (again, I don't know if this is even the right starting point). You mentioned we see objects due to light of other sources. By reflection, or by obscurity? What happens to an object at 0K that gets hit by a photon (which then is observed)? Does it remain at absolute zero? Do any atoms' electrons gain orbit?

edit: oh and thank you!

 

[Tsumi]

Okay, I'm with you so far I think. Overall I was focused on objects which would be hypotethically cooled to true zero. I should have clarified that, sorry.
So, at 0 Kelvin (theory, I know), the electron does not necessarily have to be in its lowest state, yes?



Okay, I'm still here I think Okay so let's say something is moving away from us but it's at absolute zero (again, I don't know if this is even the right starting point). You mentioned we see objects due to light of other sources. By reflection, or by obscurity? What happens to an object at 0K that gets hit by a photon (which then is observed)? Does it remain at absolute zero? Do any atoms' electrons gain orbit?

edit: oh and thank you!

Any element (or molecule) can theoretically be cooled to absolute zero. Absolute zero just means no vibration of the atom(s). The electrons do not necessarily need to be in the lowest state, true, but most likely any atom that was somehow cooled to absolute zero with an energetic electron will have the electron drop its orbital, give off radiation, and add some temperature, so such a system wouldn't be stable at all (not that absolute zero is stable in the first place anyways).

Objects in interstellar space are not at absolute zero. They vary wildly in temperature, from tens of degrees above absolute zero to thousands and millions of degrees. While it is theoretically possible that an atom in space is at 0 kelvin, in the real world it is basically impossible for atoms to be at 0 kelvin.

We see objects in space by both reflection and obscurity. It simply depends on what is going on in that particular region of space. We also see objects by gravitational lensing, where the gravitational effects of black holes and entire galaxies are used to essentially create a giant lens (bending light by gravity) to see objects behind the galaxy/black hole. However, the objects we see in space are far larger than earth, we do not have the capability of seeing other planets yet, unless they're at least as big as Jupiter and relatively close.

When a photon hits an atom, what happens depends entirely on the properties of the atom and the photon. If the photon is at the right wavelength to cause an electron to jump orbits, that's what will happen. However, the electron will drop back down almost instantaneously in most cases, emitting light. If it is not at the right wavelength to cause that, it can bounce off the atom or be absorbed by the atom and converted to thermal energy.

 

[michalrz]

Any element (or molecule) can theoretically be cooled to absolute zero. Absolute zero just means no vibration of the atom(s). The electrons do not necessarily need to be in the lowest state, true, but most likely any atom that was somehow cooled to absolute zero with an energetic electron will have the electron drop its orbital, give off radiation, and add some temperature, so such a system wouldn't be stable at all (not that absolute zero is stable in the first place anyways).

Objects in interstellar space are not at absolute zero. They vary wildly in temperature, from tens of degrees above absolute zero to thousands and millions of degrees. While it is theoretically possible that an atom in space is at 0 kelvin, in the real world it is basically impossible for atoms to be at 0 kelvin.

We see objects in space by both reflection and obscurity. It simply depends on what is going on in that particular region of space. We also see objects by gravitational lensing, where the gravitational effects of black holes and entire galaxies are used to essentially create a giant lens (bending light by gravity) to see objects behind the galaxy/black hole. However, the objects we see in space are far larger than earth, we do not have the capability of seeing other planets yet, unless they're at least as big as Jupiter and relatively close.

When a photon hits an atom, what happens depends entirely on the properties of the atom and the photon. If the photon is at the right wavelength to cause an electron to jump orbits, that's what will happen. However, the electron will drop back down almost instantaneously in most cases, emitting light. If it is not at the right wavelength to cause that, it can bounce off the atom or be absorbed by the atom and converted to thermal energy.

Thank you man. That's both terse and totally covers the bases I needed. Especially thermals vs occupied orbits.
I got hooked on questions around the time Hale-Bopp was visible. I pointed at it (I'm in a rural area so it was absolutely stunning) and said - look, that's the Hale-Bopp comet. Holy Jesus did I get ridiculed.
Now I just absorb anything really. Fooling around in LTSpice, reading, reading, reading. Could be related to how I picked up English at age seven by watching cartoon network, dunno.
Thanks!