Posts: 32878
Threads: 1409
Joined: March 15, 2013
Reputation:
152
No Big Bang?
March 13, 2018 at 7:43 pm
Saw this on another forum; thought I'd post it here.
https://m.phys.org/news/2015-02-big-quan...verse.html
Quote:Quantum equation predicts universe has no beginning
Ali and coauthor Saurya Das at the University of Lethbridge in Alberta, Canada, have shown in a paper published in Physics Letters B that the Big Bang singularity can be resolved by their new model in which the universe has no beginning and no end.
"Never trust a fox. Looks like a dog, behaves like a cat."
~ Erin Hunter
Posts: 3709
Threads: 18
Joined: September 29, 2015
Reputation:
10
RE: No Big Bang?
March 13, 2018 at 8:49 pm
(March 13, 2018 at 7:43 pm)Lutrinae Wrote: Saw this on another forum; thought I'd post it here.
https://m.phys.org/news/2015-02-big-quan...verse.html
Quote:Quantum equation predicts universe has no beginning
Ali and coauthor Saurya Das at the University of Lethbridge in Alberta, Canada, have shown in a paper published in Physics Letters B that the Big Bang singularity can be resolved by their new model in which the universe has no beginning and no end.
If you look for commentaries about this, you mostly find other articles from around 2015. And some of these articles state that this theory was very early on or as one called it “more of a proof of concept” then anything else. You don’t see much of anything since, and very little on the way of specifics. I wouldn’t get too excited just yet!
It is said that an argument is what convinces reasonable men and a proof is what it takes to convince even an unreasonable man. - Alexander Vilenkin
If I am shown my error, I will be the first to throw my books into the fire. - Martin Luther
Posts: 9848
Threads: 21
Joined: September 8, 2015
Reputation:
79
RE: No Big Bang?
March 13, 2018 at 8:50 pm
A physicist charts a bunch of data for an effect that he's studying, and goes to a mathematician for some explanation for the shape of the curve. The mathematician looks at it, and says that it's easy to write out a formula to describe that data. He starts in, but then the physicist notices that the paper is upside down. He turns it over, and the mathematician exclaims about how it's going to be easy to write out a formula for the curve!
It's a bad joke, but the point is that some of the mathematics used for this sort of thing always contains approximations based on our inability as physicists to map out ABSOLUTE TRUTH. Our equipment isn't sensitive enough to measure everything to the minutest detail, and in many cases don't even measure some things because we don't know that they are even there. We are learning as we go. We don't have all the observations for this universe, and won't be able to make them all before the universe ends...if it even does end. We have to go with whatever we can get from the data collected, so far.
If you get to thinking you’re a person of some influence, try ordering somebody else’s dog around.
Posts: 28275
Threads: 522
Joined: June 16, 2015
Reputation:
90
RE: No Big Bang?
March 13, 2018 at 8:54 pm
My god man, haven't you watched South Park? You should know that nothing good ever comes from Canada.
Being told you're delusional does not necessarily mean you're mental.
Posts: 20476
Threads: 447
Joined: June 16, 2014
Reputation:
111
RE: No Big Bang?
March 14, 2018 at 12:15 am
Kit.
You know how stars die by using up their energy...
They all die, right? They either go supernova if enough critical mass or just turn to red dwarfs.
It's just impossible for the stars we see in the sky to have been there forever.
It brings me back to infinite regress. Maybe new stars randomly appear from nothing as did matter at some point. But could matter have been there in the first place forever?
Fuck you, now I've got a headache thinking about this shit!
No God, No fear.
Know God, Know fear.
Posts: 636
Threads: 4
Joined: November 25, 2017
Reputation:
0
RE: No Big Bang?
March 17, 2018 at 5:15 am
(March 14, 2018 at 12:15 am)ignoramus Wrote: Kit.
You know how stars die by using up their energy...
They all die, right? They either go supernova if enough critical mass or just turn to red dwarfs.
It's just impossible for the stars we see in the sky to have been there forever.
It brings me back to infinite regress. Maybe new stars randomly appear from nothing as did matter at some point. But could matter have been there in the first place forever?
Fuck you, now I've got a headache thinking about this shit!
The first time nova's were discussed, it wasn't clear if a star was forming or whether it had exploded. This question has since been answered in part - with the recording of exploding stars, but there is also evidence that a cloud will collapse and reform a star, only not at the same rate of exploding. So given enough time, we may see evidence of the latter.
Some people believe that stars can explode and reform as part pf their cycles, not unlike other activities like pulsars where the temperature and light, and even size of a star oscillates.
Some of the features of stars, indicate that the sun can occasionally turn off and on again, which may be part of its system where it oscillates or flickers at specific intervals.
It is possible that stars don't die, but just experience cycles of activity, which have been measured and recorded, such as magnetic aberrations, flares, different spectrums of light, radio waves etc. And spots on our sun.
The idea of dying stars and a dying universe may just be a mortal's perspective.
Posts: 23918
Threads: 300
Joined: June 25, 2011
Reputation:
151
RE: No Big Bang?
March 17, 2018 at 6:33 am
(This post was last modified: March 17, 2018 at 6:34 am by Whateverist.)
(March 17, 2018 at 5:15 am)Banned Wrote: (March 14, 2018 at 12:15 am)ignoramus Wrote: Kit.
You know how stars die by using up their energy...
They all die, right? They either go supernova if enough critical mass or just turn to red dwarfs.
It's just impossible for the stars we see in the sky to have been there forever.
It brings me back to infinite regress. Maybe new stars randomly appear from nothing as did matter at some point. But could matter have been there in the first place forever?
Fuck you, now I've got a headache thinking about this shit!
The first time nova's were discussed, it wasn't clear if a star was forming or whether it had exploded. This question has since been answered in part - with the recording of exploding stars, but there is also evidence that a cloud will collapse and reform a star, only not at the same rate of exploding. So given enough time, we may see evidence of the latter.
Some people believe that stars can explode and reform as part pf their cycles, not unlike other activities like pulsars where the temperature and light, and even size of a star oscillates.
Some of the features of stars, indicate that the sun can occasionally turn off and on again, which may be part of its system where it oscillates or flickers at specific intervals.
It is possible that stars don't die, but just experience cycles of activity, which have been measured and recorded, such as magnetic aberrations, flares, different spectrums of light, radio waves etc. And spots on our sun.
The idea of dying stars and a dying universe may just be a mortal's perspective.
But wouldn't you agree that from the POV of a YEC it is a moot point? Anyone who thinks creation happened 6,000 years ago must believe that everything we can deduce from observations of the heavens is but a divine hoax.
Posts: 636
Threads: 4
Joined: November 25, 2017
Reputation:
0
RE: No Big Bang?
March 17, 2018 at 6:59 am
(March 17, 2018 at 6:33 am)Whateverist Wrote: But wouldn't you agree that from the POV of a YEC it is a moot point? Anyone who thinks creation happened 6,000 years ago must believe that everything we can deduce from observations of the heavens is but a divine hoax.
Yes there are a lot of objections to the creation story, but given the numerous changes in theories about the universe in only the last 180 years, there are a lot of things which we can't account for now, which may well be common knowledge in the future.
As a creationist, I don't know when the universe was created in relation to the age of the earth, but it was there before the earth was created. There are some people who say that the universe was created at the same time, but that can be shown to be false.
The Bible says that the stars were made on the 4th day, and the word for stars leans towards the meaning of planets, as written in the rest of the Torah.
One of the main objections to a young universe is the theory of light and how it reaches earth from distant objects, but there are things in the universe, similar to dark matter, which could slow the speed of light, so that what we think is really old may be a lot younger.
Another possibility is that when something is created, that it's reference of time may begin with it, so there may be no way knowing when the beginning of anything is, let alone the universe.
And the only reference anything has will be to itself.
Posts: 29592
Threads: 116
Joined: February 22, 2011
Reputation:
159
RE: No Big Bang?
March 17, 2018 at 9:00 am
(March 17, 2018 at 6:59 am)Banned Wrote: (March 17, 2018 at 6:33 am)Whateverist Wrote: But wouldn't you agree that from the POV of a YEC it is a moot point? Anyone who thinks creation happened 6,000 years ago must believe that everything we can deduce from observations of the heavens is but a divine hoax.
Yes there are a lot of objections to the creation story, but given the numerous changes in theories about the universe in only the last 180 years, there are a lot of things which we can't account for now, which may well be common knowledge in the future.
As a creationist, I don't know when the universe was created in relation to the age of the earth, but it was there before the earth was created. There are some people who say that the universe was created at the same time, but that can be shown to be false.
The Bible says that the stars were made on the 4th day, and the word for stars leans towards the meaning of planets, as written in the rest of the Torah.
One of the main objections to a young universe is the theory of light and how it reaches earth from distant objects, but there are things in the universe, similar to dark matter, which could slow the speed of light, so that what we think is really old may be a lot younger.
Another possibility is that when something is created, that it's reference of time may begin with it, so there may be no way knowing when the beginning of anything is, let alone the universe.
And the only reference anything has will be to itself.
Quote:Radioactive Dating of an Old Star
A very interesting paper by Cowan et al. (1997, ApJ, 480, 246) discusses the thorium abundance in an old halo star. Normally it is not possible to measure the abundance of radioactive isotopes in other stars because the lines are too weak. But in CS 22892-052 the thorium lines can be seen because the iron lines are very weak. The Th/Eu (Europium) ratio in this star is 0.219 compared to 0.369 in the Solar System now. Thorium decays with a half-life of 14.05 Gyr, so the Solar System formed with Th/Eu = 24.6/14.05*0.369 = 0.463. If CS 22892-052 formed with the same Th/Eu ratio it is then 15.2 +/- 3.5 Gyr old. It is actually probably slightly older because some of the thorium that would have gone into the Solar System decayed before the Sun formed, and this correction depends on the nucleosynthesis history of the Milky Way. Nonetheless, this is still an interesting measure of the age of the oldest stars that is independent of the main-sequence lifetime method.
A later paper by Cowan et al. (1999, ApJ, 521, 194) gives 15.6 +/- 4.6 Gyr for the age based on two stars: CS 22892-052 and HD 115444.
A another star, CS 31082-001, shows an age of 12.5 +/- 3 Gyr based on the decay of U-238 [Cayrel, et al. 2001, Nature, 409, 691-692]. Wanajo et al. refine the predicted U/Th production ratio and get 14.1 +/- 2.5 Gyr for the age of this star.
The Age of the Oldest Star Clusters
When stars are burning hydrogen to helium in their cores, they fall on a single curve in the luminosity-temperature plot known as the H-R diagram after its inventors, Hertzsprung and Russell. This track is known as the main sequence, since most stars are found there. Since the luminosity of a star varies like M3 or M4, the lifetime of a star on the main sequence varies like t=const*M/L=k/L0.7. Thus if you measure the luminosity of the most luminous star on the main sequence, you get an upper limit for the age of the cluster:
Age < k/L(MS_max)0.7
This is an upper limit because the absence of stars brighter than the observed L(MS_max) could be due to no stars being formed in the appropriate mass range. But for clusters with thousands of members, such a gap in the mass function is very unlikely, the age is equal to k/L(MS_max)0.7. Chaboyer, Demarque, Kernan and Krauss (1996, Science, 271, 957) apply this technique to globular clusters and find that the age of the Universe is greater than 12.07 Gyr with 95% confidence. They say the age is proportional to one over the luminosity of the RR Lyra stars which are used to determine the distances to globular clusters. Chaboyer (1997) gives a best estimate of 14.6 +/- 1.7 Gyr for the age of the globular clusters. But recent Hipparcos results show that the globular clusters are further away than previously thought, so their stars are more luminous. Gratton et al. give ages between 8.5 and 13.3 Gyr with 12.1 being most likely, while Reid gives ages between 11 and 13 Gyr, and Chaboyer et al. give 11.5 +/- 1.3 Gyr for the mean age of the oldest globular clusters.
The Age of the Oldest White Dwarfs
A white dwarf star is an object that is about as heavy as the Sun but only the radius of the Earth. The average density of a white dwarf is a million times denser than water. White dwarf stars form in the centers of red giant stars, but are not visible until the envelope of the red giant is ejected into space. When this happens the ultraviolet radiation from the very hot stellar core ionizes the gas and produces a planetary nebula. The envelope of the star continues to move away from the central core, and eventually the planetary nebula fades to invisibility, leaving just the very hot core which is now a white dwarf. White dwarf stars glow just from residual heat. The oldest white dwarfs will be the coldest and thus the faintest. By searching for faint white dwarfs, one can estimate the length of time the oldest white dwarfs have been cooling. Oswalt, Smith, Wood and Hintzen (1996, Nature, 382, 692) have done this and get an age of 9.5+1.1-0.8 Gyr for the disk of the Milky Way. They estimate an age of the Universe which is at least 2 Gyr older than the disk, so to > 11.5 Gyr.
Hansen et al. have used the HST to measure the ages of white dwarfs in the globular cluster M4, obtaining 12.7 +/- 0.7 Gyr. In 2004 Hansen et al. updated their analysis to give an age for M4 of 12.1 +/- 0.9 Gyr, which is very consistent with the age of globular clusters from the main sequence turnoff. Allowing allowing for the time between the Big Bang and the formation of globular clusters (and its uncertainty) implies an age for the Universe of 12.8 +/- 1.1 Gyr.
Age of the Universe
Posts: 11697
Threads: 117
Joined: November 5, 2016
Reputation:
43
RE: No Big Bang?
March 17, 2018 at 9:21 am
(March 17, 2018 at 9:00 am)Jörmungandr Wrote: (March 17, 2018 at 6:59 am)Banned Wrote: Yes there are a lot of objections to the creation story, but given the numerous changes in theories about the universe in only the last 180 years, there are a lot of things which we can't account for now, which may well be common knowledge in the future.
As a creationist, I don't know when the universe was created in relation to the age of the earth, but it was there before the earth was created. There are some people who say that the universe was created at the same time, but that can be shown to be false.
The Bible says that the stars were made on the 4th day, and the word for stars leans towards the meaning of planets, as written in the rest of the Torah.
One of the main objections to a young universe is the theory of light and how it reaches earth from distant objects, but there are things in the universe, similar to dark matter, which could slow the speed of light, so that what we think is really old may be a lot younger.
Another possibility is that when something is created, that it's reference of time may begin with it, so there may be no way knowing when the beginning of anything is, let alone the universe.
And the only reference anything has will be to itself.
Quote:Radioactive Dating of an Old Star
A very interesting paper by Cowan et al. (1997, ApJ, 480, 246) discusses the thorium abundance in an old halo star. Normally it is not possible to measure the abundance of radioactive isotopes in other stars because the lines are too weak. But in CS 22892-052 the thorium lines can be seen because the iron lines are very weak. The Th/Eu (Europium) ratio in this star is 0.219 compared to 0.369 in the Solar System now. Thorium decays with a half-life of 14.05 Gyr, so the Solar System formed with Th/Eu = 24.6/14.05*0.369 = 0.463. If CS 22892-052 formed with the same Th/Eu ratio it is then 15.2 +/- 3.5 Gyr old. It is actually probably slightly older because some of the thorium that would have gone into the Solar System decayed before the Sun formed, and this correction depends on the nucleosynthesis history of the Milky Way. Nonetheless, this is still an interesting measure of the age of the oldest stars that is independent of the main-sequence lifetime method.
A later paper by Cowan et al. (1999, ApJ, 521, 194) gives 15.6 +/- 4.6 Gyr for the age based on two stars: CS 22892-052 and HD 115444.
A another star, CS 31082-001, shows an age of 12.5 +/- 3 Gyr based on the decay of U-238 [Cayrel, et al. 2001, Nature, 409, 691-692]. Wanajo et al. refine the predicted U/Th production ratio and get 14.1 +/- 2.5 Gyr for the age of this star.
The Age of the Oldest Star Clusters
When stars are burning hydrogen to helium in their cores, they fall on a single curve in the luminosity-temperature plot known as the H-R diagram after its inventors, Hertzsprung and Russell. This track is known as the main sequence, since most stars are found there. Since the luminosity of a star varies like M3 or M4, the lifetime of a star on the main sequence varies like t=const*M/L=k/L0.7. Thus if you measure the luminosity of the most luminous star on the main sequence, you get an upper limit for the age of the cluster:
Age < k/L(MS_max)0.7
This is an upper limit because the absence of stars brighter than the observed L(MS_max) could be due to no stars being formed in the appropriate mass range. But for clusters with thousands of members, such a gap in the mass function is very unlikely, the age is equal to k/L(MS_max)0.7. Chaboyer, Demarque, Kernan and Krauss (1996, Science, 271, 957) apply this technique to globular clusters and find that the age of the Universe is greater than 12.07 Gyr with 95% confidence. They say the age is proportional to one over the luminosity of the RR Lyra stars which are used to determine the distances to globular clusters. Chaboyer (1997) gives a best estimate of 14.6 +/- 1.7 Gyr for the age of the globular clusters. But recent Hipparcos results show that the globular clusters are further away than previously thought, so their stars are more luminous. Gratton et al. give ages between 8.5 and 13.3 Gyr with 12.1 being most likely, while Reid gives ages between 11 and 13 Gyr, and Chaboyer et al. give 11.5 +/- 1.3 Gyr for the mean age of the oldest globular clusters.
The Age of the Oldest White Dwarfs
A white dwarf star is an object that is about as heavy as the Sun but only the radius of the Earth. The average density of a white dwarf is a million times denser than water. White dwarf stars form in the centers of red giant stars, but are not visible until the envelope of the red giant is ejected into space. When this happens the ultraviolet radiation from the very hot stellar core ionizes the gas and produces a planetary nebula. The envelope of the star continues to move away from the central core, and eventually the planetary nebula fades to invisibility, leaving just the very hot core which is now a white dwarf. White dwarf stars glow just from residual heat. The oldest white dwarfs will be the coldest and thus the faintest. By searching for faint white dwarfs, one can estimate the length of time the oldest white dwarfs have been cooling. Oswalt, Smith, Wood and Hintzen (1996, Nature, 382, 692) have done this and get an age of 9.5+1.1-0.8 Gyr for the disk of the Milky Way. They estimate an age of the Universe which is at least 2 Gyr older than the disk, so to > 11.5 Gyr.
Hansen et al. have used the HST to measure the ages of white dwarfs in the globular cluster M4, obtaining 12.7 +/- 0.7 Gyr. In 2004 Hansen et al. updated their analysis to give an age for M4 of 12.1 +/- 0.9 Gyr, which is very consistent with the age of globular clusters from the main sequence turnoff. Allowing allowing for the time between the Big Bang and the formation of globular clusters (and its uncertainty) implies an age for the Universe of 12.8 +/- 1.1 Gyr.
Age of the Universe Now watch him dismiss all that .
Seek strength, not to be greater than my brother, but to fight my greatest enemy -- myself.
Inuit Proverb
|