Is the universe expanding or are we shrinking?
[quote name='EnigmaticProgrammer' timesta
Again I disagree. The universe started out very hot (entropy) and over time it has lost entropy. In the future the universe will become more ordered. The reason for this is a concept known as emergence. Please watch this video for a better understanding. Evidence for emergence can be seen all around us but the increase in entropy as time moves forward has no evidence.
I like to think of the universe as a snowflake:
Each new branch is a new universe formed through a black hole. As time moves forward entropy is lost and order is increased. Eventually order will become so great that there is nothing but black holes in the universe and these black holes will interact with each other to form a much larger and more complex system. This process of complexification likely continues in to infinity.
Also the way you are looking at entropy is wrong. Entropy is not disorder.
[/quote]
I'm sorry - to me this is not a matter of agreeing or disagreeing. The fact that you're saying the universe is moving towards a state of increased order (as opposed to disorder) is just plain wrong. If anything, perhaps you should please read some of the links I provided. It may boil down to the technicality of language and misunderstanding, but the bottom line is that black holes have the highest known entropy in our universe.
To address the term "entropy is not disorder" - you're right, entropy is the measure of order/disorder (so you're using the word incorrectly as well in sentences like "... started out very hot (entropy) and ..."). Simple evidence that the universe started out in a high state of order (low entropy) is carried by the fact that it's relatively (in fact, without quantum mechanics would be perfectly) uniform. For instance, microwave background radiation was theorized, but couldn't be detected for the longest time, because it's so uniform. This all points to the fact that the early universe was an almost uniform mass of particles that only began to break down and gain entropy because of quantum jitters (click) that slowly broke the homogeneity, causing a snowball effect. Even the presumed massive expansion (a.k.a. hyperinflation) at the very early stages of the universe would otherwise not have been able to disrupt the order enough (enough meaning "at all" in this case) to cause matter to start to clump up.
What Neil Degrasse Tyson is talking about is another type of order - the type of "order" that living organisms require. When compared to the kind of order described by entropy, the word "complexity" itself contradicts the word "order".
To put this to rest: the universe is tending towards maximum entropy.
I can suggest a few books if you're interested about this, but what you wrote in your last response is, I'm sorry, completely backwards to how science has it.
Again I disagree. The universe started out very hot (entropy) and over time it has lost entropy. In the future the universe will become more ordered. The reason for this is a concept known as emergence. Please watch this video for a better understanding. Evidence for emergence can be seen all around us but the increase in entropy as time moves forward has no evidence.
I like to think of the universe as a snowflake:
Each new branch is a new universe formed through a black hole. As time moves forward entropy is lost and order is increased. Eventually order will become so great that there is nothing but black holes in the universe and these black holes will interact with each other to form a much larger and more complex system. This process of complexification likely continues in to infinity.
Also the way you are looking at entropy is wrong. Entropy is not disorder.
[/quote]
I'm sorry - to me this is not a matter of agreeing or disagreeing. The fact that you're saying the universe is moving towards a state of increased order (as opposed to disorder) is just plain wrong. If anything, perhaps you should please read some of the links I provided. It may boil down to the technicality of language and misunderstanding, but the bottom line is that black holes have the highest known entropy in our universe.
To address the term "entropy is not disorder" - you're right, entropy is the measure of order/disorder (so you're using the word incorrectly as well in sentences like "... started out very hot (entropy) and ..."). Simple evidence that the universe started out in a high state of order (low entropy) is carried by the fact that it's relatively (in fact, without quantum mechanics would be perfectly) uniform. For instance, microwave background radiation was theorized, but couldn't be detected for the longest time, because it's so uniform. This all points to the fact that the early universe was an almost uniform mass of particles that only began to break down and gain entropy because of quantum jitters (click) that slowly broke the homogeneity, causing a snowball effect. Even the presumed massive expansion (a.k.a. hyperinflation) at the very early stages of the universe would otherwise not have been able to disrupt the order enough (enough meaning "at all" in this case) to cause matter to start to clump up.
What Neil Degrasse Tyson is talking about is another type of order - the type of "order" that living organisms require. When compared to the kind of order described by entropy, the word "complexity" itself contradicts the word "order".
To put this to rest: the universe is tending towards maximum entropy.
I can suggest a few books if you're interested about this, but what you wrote in your last response is, I'm sorry, completely backwards to how science has it.
I'm sorry - to me this is not a matter of agreeing or disagreeing. The fact that you're saying the universe is moving towards a state of increased order (as opposed to disorder) is just plain wrong. If anything, perhaps you should please read some of the links I provided. It may boil down to the technicality of language and misunderstanding, but the bottom line is that black holes have the highest known entropy in our universe.
To address the term "entropy is not disorder" - you're right, entropy is the measure of order/disorder (so you're using the word incorrectly as well in sentences like "... started out very hot (entropy) and ..."). Simple evidence that the universe started out in a high state of order (low entropy) is carried by the fact that it's relatively (in fact, without quantum mechanics would be perfectly) uniform. For instance, microwave background radiation was theorized, but couldn't be detected for the longest time, because it's so uniform. This all points to the fact that the early universe was an almost uniform mass of particles that only began to break down and gain entropy because of quantum jitters (click) that slowly broke the homogeneity, causing a snowball effect. Even the presumed massive expansion (a.k.a. hyperinflation) at the very early stages of the universe would otherwise not have been able to disrupt the order enough (enough meaning "at all" in this case) to cause matter to start to clump up.
What Neil Degrasse Tyson is talking about is another type of order - the type of "order" that living organisms require. When compared to the kind of order described by entropy, the word "complexity" itself contradicts the word "order".
To put this to rest: the universe is tending towards maximum entropy.
I can suggest a few books if you're interested about this, but what you wrote in your last response is, I'm sorry, completely backwards to how science has it.
You are right that it does not conform with the models which have been previously built and it is not suppose to. The universe is becoming more ordered with time inspire of what you or others believe. Initially the universe was a chaotic soup of particles. These particles grouped together to form larger more complex particles which in turn grouped together to form stars. Some stars collapsed to from black holes which then formed galaxies.
These stars then produced all of the elements of the periodic table which produced planets, meteors, and comets. The chemicals on some planets then grouped together to form simple proteins which then grouped together to form a single celled organism. Cells then grouped together to form larger more complex systems. Now we have human minds grouping together to from a greater consciousness known as the internet. There is no way you can convince me that the universe is not becoming more ordered with time.
There is no way you can convince me that the universe is not becoming more ordered with time.
Ok.
[quote name='EnigmaticProgrammer' timestamp='1335782136' post='4936036']
There is no way you can convince me that the universe is not becoming more ordered with time.
Ok.
[/quote]
Perhaps I see order as structure and you see it as uniformity. I see what you are saying but it has nothing to do with what I'm talking about. Maybe this will explain what I'm talking about.
[quote name='irreversible' timestamp='1335772689' post='4936011']
I'm sorry - to me this is not a matter of agreeing or disagreeing. The fact that you're saying the universe is moving towards a state of increased order (as opposed to disorder) is just plain wrong. If anything, perhaps you should please read some of the links I provided. It may boil down to the technicality of language and misunderstanding, but the bottom line is that black holes have the highest known entropy in our universe.
To address the term "entropy is not disorder" - you're right, entropy is the measure of order/disorder (so you're using the word incorrectly as well in sentences like "... started out very hot (entropy) and ..."). Simple evidence that the universe started out in a high state of order (low entropy) is carried by the fact that it's relatively (in fact, without quantum mechanics would be perfectly) uniform. For instance, microwave background radiation was theorized, but couldn't be detected for the longest time, because it's so uniform. This all points to the fact that the early universe was an almost uniform mass of particles that only began to break down and gain entropy because of quantum jitters (click) that slowly broke the homogeneity, causing a snowball effect. Even the presumed massive expansion (a.k.a. hyperinflation) at the very early stages of the universe would otherwise not have been able to disrupt the order enough (enough meaning "at all" in this case) to cause matter to start to clump up.
What Neil Degrasse Tyson is talking about is another type of order - the type of "order" that living organisms require. When compared to the kind of order described by entropy, the word "complexity" itself contradicts the word "order".
To put this to rest: the universe is tending towards maximum entropy.
I can suggest a few books if you're interested about this, but what you wrote in your last response is, I'm sorry, completely backwards to how science has it.
You are right that it does not conform with the models which have been previously built and it is not suppose to. The universe is becoming more ordered with time inspire of what you or others believe. Initially the universe was a chaotic soup of particles. These particles grouped together to form larger more complex particles which in turn grouped together to form stars. Some stars collapsed to from black holes which then formed galaxies.
These stars then produced all of the elements of the periodic table which produced planets, meteors, and comets. The chemicals on some planets then grouped together to form simple proteins which then grouped together to form a single celled organism. Cells then grouped together to form larger more complex systems. Now we have human minds grouping together to from a greater consciousness known as the internet. There is no way you can convince me that the universe is not becoming more ordered with time.
[/quote]
What. These events pale into insignificance when you consider the energy expended getting them that way. The WWW consumes ~1 tera Wh per year. Yes, some order is formed by someone posting a nyan cat onto 4chan, but lots more disorder is created in the universe at large. His computer blows hot air around the room. A nearby power station burns oil or whatever to power his house, in fact, several hundred have to be operating to power all the servers. Don't confuse thermodynamic entropy with "this seashell is a pretty shape"
For fun:
- The universe is expanding. If you were instead shrinking, then all light from all galaxies would appear redshifted by the same amount, which is obviously not the case. Work it out in your head.
- Eye vs universe movement: Mach's principle as applied by Einstein in general relativity basically says that it's most likely that the eye is moving. Inertia there defines inertia here. So, what's most likely to happen: A tiny bit of energy was used to overcome the inertia of an eyeball, or a ridiculous amount of energy was used to overcome the inertia of everything else in the universe (and all at once)? It is most likely that the eye moved. Same for Newton's bucket full of water, and spinning figure skaters.
- Baby universes in black holes: Consider that the original papers on holographic principle went out of their way to make it perfectly clear that you cannot create a "universe packed into a test tube". You simply cannot pack that much information into that small of a space. As for circumventing this by assuming that new space is being created inside of a black hole, the jury's obviously still out on that one. For all we know, the "white hole" that appears in the Kruskal-Szekeres coordinates is simply a bogus artifact of our less-than-perfect way of doing mathematics and physics in general. Just keep in mind that the person who went to so much trouble to publicize the idea of baby universes sprouting out of white holes was the same person who thought that information could be destroyed. He was wrong, and even he admits it now.
- Entropy: It took time for the various different types of fundamental particles to come into existence after the Big Bang, as you fully admit. Simply consider that it took a non-zero amount of time for quarks to form, and it took an even larger non-zero amount of time for the quarks to be able to finally form the bound states commonly known as protons and neutrons. A larger number of different types of allowed particles means a larger number of states for the universe's energy to be found in. Larger number of allowed states that are filled, larger entropy.
In terms of plain old digital computers, how many states are an 8-bit integer most often to be found in? 256. And a 16-bit integer? 65,536. Larger number of allowed states that are filled, larger entropy. For the 8-bit integer, the binary entropy is S = ln(256)/ln(2) = 8. For the 16-bit integer, it's S = ln(65536)/ln(2) = 16.
Consider that the mass-energy that you're made of is not all completely entangled (in the quantum sense). Now make yourself into a black hole, so that all of your mass-energy is completely entangled. These new entanglement relationships alone would require new information in order to describe you in your entirety. Information is entropy, and it certainly did not decrease when you transformed into a black hole. See: http://en.wikipedia....glement#Entropy for an explanation of the entropy-entanglement relationship. I'm not a professional physicist, and my explanation might be a little crude, but I'm sure that you get the idea. If anyone wishes to refute what I've said here, then I kindly ask that they put forth an argument in terms of states and information (ie. the tried and true, original, often imitated but never duplicated, definition of entropy).
I won't be making a habit of posting in the lounge, but this topic is just too fun to pass on.
- The universe is expanding. If you were instead shrinking, then all light from all galaxies would appear redshifted by the same amount, which is obviously not the case. Work it out in your head.
- Eye vs universe movement: Mach's principle as applied by Einstein in general relativity basically says that it's most likely that the eye is moving. Inertia there defines inertia here. So, what's most likely to happen: A tiny bit of energy was used to overcome the inertia of an eyeball, or a ridiculous amount of energy was used to overcome the inertia of everything else in the universe (and all at once)? It is most likely that the eye moved. Same for Newton's bucket full of water, and spinning figure skaters.
- Baby universes in black holes: Consider that the original papers on holographic principle went out of their way to make it perfectly clear that you cannot create a "universe packed into a test tube". You simply cannot pack that much information into that small of a space. As for circumventing this by assuming that new space is being created inside of a black hole, the jury's obviously still out on that one. For all we know, the "white hole" that appears in the Kruskal-Szekeres coordinates is simply a bogus artifact of our less-than-perfect way of doing mathematics and physics in general. Just keep in mind that the person who went to so much trouble to publicize the idea of baby universes sprouting out of white holes was the same person who thought that information could be destroyed. He was wrong, and even he admits it now.
- Entropy: It took time for the various different types of fundamental particles to come into existence after the Big Bang, as you fully admit. Simply consider that it took a non-zero amount of time for quarks to form, and it took an even larger non-zero amount of time for the quarks to be able to finally form the bound states commonly known as protons and neutrons. A larger number of different types of allowed particles means a larger number of states for the universe's energy to be found in. Larger number of allowed states that are filled, larger entropy.
In terms of plain old digital computers, how many states are an 8-bit integer most often to be found in? 256. And a 16-bit integer? 65,536. Larger number of allowed states that are filled, larger entropy. For the 8-bit integer, the binary entropy is S = ln(256)/ln(2) = 8. For the 16-bit integer, it's S = ln(65536)/ln(2) = 16.
Consider that the mass-energy that you're made of is not all completely entangled (in the quantum sense). Now make yourself into a black hole, so that all of your mass-energy is completely entangled. These new entanglement relationships alone would require new information in order to describe you in your entirety. Information is entropy, and it certainly did not decrease when you transformed into a black hole. See: http://en.wikipedia....glement#Entropy for an explanation of the entropy-entanglement relationship. I'm not a professional physicist, and my explanation might be a little crude, but I'm sure that you get the idea. If anyone wishes to refute what I've said here, then I kindly ask that they put forth an argument in terms of states and information (ie. the tried and true, original, often imitated but never duplicated, definition of entropy).
I won't be making a habit of posting in the lounge, but this topic is just too fun to pass on.
- The universe is expanding. If you were instead shrinking, then all light from all galaxies would appear redshifted by the same amount, which is obviously not the case. Work it out in your head.
Actually I think you are forgetting a phenomenon in physics called gravitational redshift. Whether the universe is expanding or shrinking it is clear that the universe is much less dense than it was. A beam of light traveling through empty space would encounter much less time distortion as bodies of matter collapse in on themselves. Since words are rarely enough to explain a concept such as this I have created an image to help you understand:
[attachment=8816:Untitled.jpg]
Imagine the black is gravity and the white is empty space. The top of the picture is earlier in time and the bottom is later. As bodies become further and further away from each other the beam of light encounters less and less gravity which gives it a red shift.
A beam of light traveling through empty space would encounter much less time distortion as bodies of matter collapse in on themselves.
Considering that "empty" space betwen galaxies has been practically "empty" for most of the lifetime of the universe, and that redshift is still very much occurring and -- somewhat recently in comparison to the lifetime of the universe -- in an accelerating way, what you are talking about is practically inconsequential to what we are talking about here, so I'm not sure why you brought it up. That said: the metric of "empty" space(-time) surrounding an idealized non-rotating star of 20 solar masses is essentially the same as the metric of "empty" space(-time) surrounding an idealized non-rotating black hole of 20 solar masses. See Birkhoff's theorem for an explanation of why a rapidly pulsating spherical body would not give off gravitational radiation -- the metric is essentially time-independent, even though the radius of the body is changing rapidly. In other words, the metric of "empty" space(-time) at long distance doesn't really change when the body is shrunk. This is all pretty much manifest even in Newton's somewhat ancient shell theorem, if you think about it.
Also keep in mind that someone on the surface of a "planet" of this constant radius or that constant radius who is shooting red photons out into outer space will always be shooting out red photons -- in terms of their local measures of space and time. Globally, the photons being shot out would obviously be bluer and bluer for smaller and smaller radii, thanks to the increasing amount of gravitational time dilation at the surface. In the end though, it all works out to be the same frequency when the photons are observed at long distance. If you were to tell someone to go to this planet or that planet and tell them to shoot red photons at Earth, you will simply would not be able to tell the amount of gravitational time dilation at the surface of this planet or that planet that they were standing on when you receive their photons at long distance -- they would all be red. Perhaps this is exactly where you and I disagree, and perhaps I'm wrong, but I'm thinking that gravitational redshift and Doppler redshift are being confused here. Yes, oscillators in the vicinity of a black hole event horizon effectively oscillate slower due to gravitational time dilation, but you also have to consider that space is more compact there, so the distance of the oscillation effectively shrinks to perfectly compensate.
Now, in your non-expanding universe, the inward movement of the shooter that is caused by the contraction of the surface would be the only source of detectable redshift at long distance. And so, if all planets were shrinking at the same rate, then all photons being shot out from all planets would all be Doppler redshifted by the same amount. I mean, when you read stories about what would happen if you saw someone falling into a black hole, the key word is falling, which implies movement and Doppler redshift.
Again, does any of this really have to do with shinking Planck scale / static universe vs. static Planck scale / expanding universe? Probably not. Do consider this though: A shrinking Planck length would automatically mean a shrinking Planck time. If anything, a metric expansion of space would presumably be related to a contraction / shrinking / speeding up of time. Is this what you were trying to say? Do we really have evidence that time is speeding up (and in an accelerated way)? Regardless, do you see now how the two things -- a changing Planck scale and a changing universe scale -- are not really opposites? Both space and time would do exactly the same thing (ie. shrink) in the Planck scenario, but both space and time would most certainly not do the same thing in the expanding universe scenario. They're not analogous scenarios (in reverse), wouldn't you agree?
This is all precisely why I think that the metric expansion of space is the only viable option for explaining galactic redshift. Thanks for your patience while I worked on this post. It only took me 60+ edits to tweak it. I guess you could say that I have "thought -> keyboard issues". ;)
[quote name='EnigmaticProgrammer' timestamp='1336728694' post='4939245']
A beam of light traveling through empty space would encounter much less time distortion as bodies of matter collapse in on themselves.
Considering that "empty" space betwen galaxies has been practically "empty" for most of the lifetime of the universe, and that redshift is still very much occurring and -- somewhat recently in comparison to the lifetime of the universe -- in an accelerating way, what you are talking about is practically inconsequential to what we are talking about here, so I'm not sure why you brought it up. That said: the metric of "empty" space(-time) surrounding an idealized non-rotating star of 20 solar masses is essentially the same as the metric of "empty" space(-time) surrounding an idealized non-rotating black hole of 20 solar masses. See Birkhoff's theorem for an explanation of why a rapidly pulsating spherical body would not give off gravitational radiation -- the metric is essentially time-independent, even though the radius of the body is changing rapidly. In other words, the metric of "empty" space(-time) at long distance doesn't really change when the body is shrunk. This is all pretty much manifest even in Newton's somewhat ancient shell theorem, if you think about it.
Also keep in mind that someone on the surface of a "planet" of this constant radius or that constant radius who is shooting red photons out into outer space will always be shooting out red photons -- in terms of their local measures of space and time. Globally, the photons being shot out would obviously be bluer and bluer for smaller and smaller radii, thanks to the increasing amount of gravitational time dilation at the surface. In the end though, it all works out to be the same frequency when the photons are observed at long distance. If you were to tell someone to go to this planet or that planet and tell them to shoot red photons at Earth, you will simply would not be able to tell the amount of gravitational time dilation at the surface of this planet or that planet that they were standing on when you receive their photons at long distance -- they would all be red. Perhaps this is exactly where you and I disagree, and perhaps I'm wrong, but I'm thinking that gravitational redshift and Doppler redshift are being confused here. Yes, oscillators in the vicinity of a black hole event horizon effectively oscillate slower due to gravitational time dilation, but you also have to consider that space is more compact there, so the distance of the oscillation effectively shrinks to perfectly compensate.
Now, in your non-expanding universe, the inward movement of the shooter that is caused by the contraction of the surface would be the only source of detectable redshift at long distance. And so, if all planets were shrinking at the same rate, then all photons being shot out from all planets would all be Doppler redshifted by the same amount. I mean, when you read stories about what would happen if you saw someone falling into a black hole, the key word is falling, which implies movement and Doppler redshift.
Again, does any of this really have to do with shinking Planck scale / static universe vs. static Planck scale / expanding universe? Probably not. Do consider this though: A shrinking Planck length would automatically mean a shrinking Planck time. If anything, a metric expansion of space would presumably be related to a contraction / shrinking / speeding up of time. Is this what you were trying to say? Do we really have evidence that time is speeding up (and in an accelerated way)? Regardless, do you see now how the two things -- a changing Planck scale and a changing universe scale -- are not really opposites? Both space and time would do exactly the same thing (ie. shrink) in the Planck scenario, but both space and time would most certainly not do the same thing in the expanding universe scenario. They're not analogous scenarios (in reverse), wouldn't you agree?
This is all precisely why I think that the metric expansion of space is the only viable option for explaining galactic redshift. Thanks for your patience while I worked on this post. It only took me 60+ edits to tweak it. I guess you could say that I have "thought -> keyboard issues". ;)
[/quote]
To the contrary, I am suggesting that time is actually slowing down. I think the problem is that you are thinking with the mind set that the universe is expanding. Most of the theories you have presented only apply and were created based on that assumption.
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