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No. As described above, most stars end up as brown dwarfs, white dwarfs, or neutron stars, which are ejected from their galaxies. A body like a brown dwarf will gradually lose its atoms to the interstellar medium. Due to some counterintuitive thermodynamics, theythese atoms are probably eventually spontaneously ionized (Baez 2004). Baez gives a general argument that takes into account the cosmological environment, but to get the basic idea, I like the following argument given by Peierls 1979. Take a gas of hydrogen atoms. The sum $Z=\Sigma_{n=0}^\infty e^{-\beta E_n}$ diverges, so in the limit of low concentration, where $n$ can go arbitrarily high, the probability of any discrete state is zero.) Although the temperature is also going down over time, it reaches a finite limit, which is set by the Hawking radiation associated with the cosmological horizon.

No. As described above, most stars end up as brown dwarfs, white dwarfs, or neutron stars, which are ejected from their galaxies. Due to some counterintuitive thermodynamics, they are probably eventually spontaneously ionized (Baez 2004). Baez gives a general argument that takes into account the cosmological environment, but to get the basic idea, I like the following argument given by Peierls 1979. Take a gas of hydrogen atoms. The sum $Z=\Sigma_{n=0}^\infty e^{-\beta E_n}$ diverges, so in the limit of low concentration, where $n$ can go arbitrarily high, the probability of any discrete state is zero.)

No. As described above, most stars end up as brown dwarfs, white dwarfs, or neutron stars, which are ejected from their galaxies. A body like a brown dwarf will gradually lose its atoms to the interstellar medium. Due to some counterintuitive thermodynamics, these atoms are probably eventually spontaneously ionized (Baez 2004). Baez gives a general argument that takes into account the cosmological environment, but to get the basic idea, I like the following argument given by Peierls 1979. Take a gas of hydrogen atoms. The sum $Z=\Sigma_{n=0}^\infty e^{-\beta E_n}$ diverges, so in the limit of low concentration, where $n$ can go arbitrarily high, the probability of any discrete state is zero. Although the temperature is also going down over time, it reaches a finite limit, which is set by the Hawking radiation associated with the cosmological horizon.

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No. As described above, most stars end up as brown dwarfs, white dwarfs, or neutron stars, which are ejected from their galaxies. Due to some counterintuitive thermodynamics, they are probably eventually spontaneously ionized (Baez 2004). Baez gives a general argument that takes into account the cosmological environment, but to get the basic idea, I like the following argument given by Peierls 1979. Take a gas of hydrogen atoms. The sum $Z=\Sigma_{n=0}^\infty e^{-\beta E_n}$ diverges, so in the limit of low concentration, where $n$ can go arbitrarily high, the probability of any discrete state is zero.)

This suppliesionization turns our dead stars into a population of unbound massive particles, which adds in to the population of such particles that simply never happened to undergo gravitational collapse into a macroscopic body. (If proton decay exists, then it modifies this picture somewhat, e.g., neutron stars evolve in certain ways, but the end result should be the same.)

Krauss and Starkman, 1999, Life, The Universe, and Nothing: Life and Death in an Ever-Expanding Universe, http://arxiv.org/abs/astro-ph/9902189

Peierls, Surprises in Theoretical Physics, section 3.2

No. As described above, most stars end up as brown dwarfs, white dwarfs, or neutron stars, which are ejected from their galaxies. Due to some counterintuitive thermodynamics, they are probably eventually spontaneously ionized (Baez 2004). This supplies a population of unbound massive particles, which adds in to the population of such particles that simply never happened to undergo gravitational collapse into a macroscopic body. (If proton decay exists, then it modifies this picture somewhat, e.g., neutron stars evolve in certain ways, but the end result should be the same.)

Krauss and Starkman, 1999, Life, The Universe, and Nothing: Life and Death in an Ever-Expanding Universe, http://arxiv.org/abs/astro-ph/9902189

No. As described above, most stars end up as brown dwarfs, white dwarfs, or neutron stars, which are ejected from their galaxies. Due to some counterintuitive thermodynamics, they are probably eventually spontaneously ionized (Baez 2004). Baez gives a general argument that takes into account the cosmological environment, but to get the basic idea, I like the following argument given by Peierls 1979. Take a gas of hydrogen atoms. The sum $Z=\Sigma_{n=0}^\infty e^{-\beta E_n}$ diverges, so in the limit of low concentration, where $n$ can go arbitrarily high, the probability of any discrete state is zero.)

This ionization turns our dead stars into a population of unbound massive particles, which adds in to the population of such particles that simply never happened to undergo gravitational collapse into a macroscopic body. (If proton decay exists, then it modifies this picture somewhat, e.g., neutron stars evolve in certain ways, but the end result should be the same.)

Krauss and Starkman, 1999, Life, The Universe, and Nothing: Life and Death in an Ever-Expanding Universe, http://arxiv.org/abs/astro-ph/9902189

Peierls, Surprises in Theoretical Physics, section 3.2

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You can get some variation in the above story if you make unusual assumptions about the equation of state for dark energy. Baez, for example, seems to be implicitly assuming that dark energy acts like a cosmological constant, which is the most conservative interpretation right now. But, e.g., it's possible under other assumptions to have a "big rip" scenario.

There seem to be a huge number of people on the internet who believe that the universe of the far future will consist of nothing but photons, since all matter will have been recycled through black holes and Hawking radiation. The above analysis shows that this is simply untrue, but this folk belief seems to have the same kind of grip on the popular consciousness as other false factoids such as Eskimos' having $n$ words for snow or the belief that people should drink eight glasses of water a day. One reason we can be very sure that the claim about photons is not true is that Roger Penrose is a very smart guy, and he had a theory called conformal cyclic cosmology (CCC) which only seemed to be viable if he could find a way to get all matter to be recycled into photons in the distant future. This gave him the strongest possible motivation to look for mechanisms to make that happen, and after considerable (publicized) effort, he failed.

There seem to be a huge number of people on the internet who believe that the universe of the far future will consist of nothing but photons, since all matter will have been recycled through black holes and Hawking radiation. The above analysis shows that this is simply untrue, but this folk belief seems to have the same kind of grip on the popular consciousness as other false factoids such as Eskimos' having $n$ words for snow or the belief that people should drink eight glasses of water a day. One reason we can be very sure that the claim about photons is not true is that Roger Penrose is a very smart guy, and he had a theory called conformal cyclic cosmology (CCC) which only seemed to be viable if he could find a way to get all matter to be recycled into photons in the distant future. This gave him the strongest possible motivation to look for mechanisms to make that happen, and after considerable (publicized) effort, he failed.

You can get some variation in the above story if you make unusual assumptions about the equation of state for dark energy. Baez, for example, seems to be implicitly assuming that dark energy acts like a cosmological constant, which is the most conservative interpretation right now. But, e.g., it's possible under other assumptions to have a "big rip" scenario.

There seem to be a huge number of people on the internet who believe that the universe of the far future will consist of nothing but photons, since all matter will have been recycled through black holes and Hawking radiation. The above analysis shows that this is simply untrue, but this folk belief seems to have the same kind of grip on the popular consciousness as other false factoids such as Eskimos' having $n$ words for snow or the belief that people should drink eight glasses of water a day. One reason we can be very sure that the claim about photons is not true is that Roger Penrose is a very smart guy, and he had a theory called conformal cyclic cosmology (CCC) which only seemed to be viable if he could find a way to get all matter to be recycled into photons in the distant future. This gave him the strongest possible motivation to look for mechanisms to make that happen, and after considerable (publicized) effort, he failed.

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