Dark Matter possibly preceded the Big Bang by ~3 billion years.
https://www.techexplorist.com/dark-matter-existed-before-big-bang-study/25576/
In the above article it says that dark matter preceded the big bang. The article never says how many billions of years that dark matter may have preceded the big bang. I supposed that dark matter is what enabled the universe to get past the intense gravity of the initial big bang event. Please read the article before commenting.
Questions and Comments?
___________________
Dark matter may have existed before the big bang, study
Testing the origin of dark matter by observing the signatures dark matter leaves on the distribution of matter in the universe.
_________________
One of the mysteries of our universe is that of dark energy and dark matter. Scientists all over the world are attempting to discover what particles make up dark energy and matter. However, it is believed that dark matter makes up about 80% of the universe’s mass.
However, it is believed that dark matter makes up about 80% of the universe’s mass. But a new study by scientists at Johns Hopkins University, suggests that dark matter may have existed before the Big Bang.
The study also represents a new idea of how dark matter was conceived and how to distinguish it with galactic observations.
Tommi Tenkanen, a postdoctoral fellow in Physics and Astronomy at the Johns Hopkins University, said, “The study revealed a new connection between particle physics and astronomy. If dark matter consists of new particles that were born before the Big Bang, they affect the way galaxies are uniquely distributed in the sky. This connection may be used to reveal their identity and make conclusions about the times before the Big Bang too.”
Well, the origin of dark matter is still a mystery, yet astronomers have shown dark matter assumes a vital role in the formation of galaxies and galaxy clusters. Despite the fact that not legitimately observable, scientists know dark matter exists by its gravitational energy consequences for how visible matter moves and is dispersed in space.
For quite a while, scientists believed that dark matter must be an extra substance from the Big Bang. Specialists have long looked for this sort of dark matter, however, so far every trial search has been fruitless.
Tenkanen said, “If dark matter were truly a remnant of the Big Bang, then in many cases researchers should have seen a direct signal of dark matter in different particle physics experiments already.”
For this study, scientists used a simple mathematical system and suggested that the dark matter has emerged before the Big Bang. It might be formed during an era known as cosmic inflation when space was expanding very rapidly.
Tenkanen said, “With the proposed mathematical scenario, we don’t have to assume new types of interactions between visible and dark matter beyond gravity, which we already know is there.”
“While the idea that dark matter existed before the Big Bang is not new, other theorists have not been able to come up with calculations that support the idea. The new study shows that researchers have always overlooked the simplest possible mathematical scenario for dark matter’s origins.”
“While this type of dark matter is too elusive to be found in particle experiments, it can reveal its presence in astronomical observations. We will soon learn more about the origin of dark matter when the Euclid satellite is launched in 2022. It’s going to be very exciting to see what it will reveal about dark matter and if its findings can be used to peak into the times before the Big Bang.”
In the above article it says that dark matter preceded the big bang. The article never says how many billions of years that dark matter may have preceded the big bang. I supposed that dark matter is what enabled the universe to get past the intense gravity of the initial big bang event. Please read the article before commenting.
Questions and Comments?
___________________
Dark matter may have existed before the big bang, study
Testing the origin of dark matter by observing the signatures dark matter leaves on the distribution of matter in the universe.
_________________
One of the mysteries of our universe is that of dark energy and dark matter. Scientists all over the world are attempting to discover what particles make up dark energy and matter. However, it is believed that dark matter makes up about 80% of the universe’s mass.
However, it is believed that dark matter makes up about 80% of the universe’s mass. But a new study by scientists at Johns Hopkins University, suggests that dark matter may have existed before the Big Bang.
The study also represents a new idea of how dark matter was conceived and how to distinguish it with galactic observations.
Tommi Tenkanen, a postdoctoral fellow in Physics and Astronomy at the Johns Hopkins University, said, “The study revealed a new connection between particle physics and astronomy. If dark matter consists of new particles that were born before the Big Bang, they affect the way galaxies are uniquely distributed in the sky. This connection may be used to reveal their identity and make conclusions about the times before the Big Bang too.”
Well, the origin of dark matter is still a mystery, yet astronomers have shown dark matter assumes a vital role in the formation of galaxies and galaxy clusters. Despite the fact that not legitimately observable, scientists know dark matter exists by its gravitational energy consequences for how visible matter moves and is dispersed in space.
For quite a while, scientists believed that dark matter must be an extra substance from the Big Bang. Specialists have long looked for this sort of dark matter, however, so far every trial search has been fruitless.
Tenkanen said, “If dark matter were truly a remnant of the Big Bang, then in many cases researchers should have seen a direct signal of dark matter in different particle physics experiments already.”
For this study, scientists used a simple mathematical system and suggested that the dark matter has emerged before the Big Bang. It might be formed during an era known as cosmic inflation when space was expanding very rapidly.
Tenkanen said, “With the proposed mathematical scenario, we don’t have to assume new types of interactions between visible and dark matter beyond gravity, which we already know is there.”
“While the idea that dark matter existed before the Big Bang is not new, other theorists have not been able to come up with calculations that support the idea. The new study shows that researchers have always overlooked the simplest possible mathematical scenario for dark matter’s origins.”
“While this type of dark matter is too elusive to be found in particle experiments, it can reveal its presence in astronomical observations. We will soon learn more about the origin of dark matter when the Euclid satellite is launched in 2022. It’s going to be very exciting to see what it will reveal about dark matter and if its findings can be used to peak into the times before the Big Bang.”
Comments (60)
What justifies your "~3 billion years" if it is not mentioned in the article?
Oh i forgot that a guy by Haim Shore came to that conclusion from studying ancient Hebrew and the book of Genesis.
Actually no i don't necessarily believe that God is dark matter. I do believe in pan-psychism (there are over 11 forms). Did you read the article?
for whatever reason this post will probably be taken down due to supposed "poor quality".
I'm sure they'll give me a poor reason for why it had to be taken down.
For fuck's sake.
the forum moderators say i have to turn the other cheek 100% of the time. so:
thats fair.
The article is saying that dark matter was possibly around already before that phase shift. Which isn't very surprising, since it's apparently some kind of stuff very different from the stuff made of excitations of quantum fields that we're familiar with.
I think the thing that maybe interests you about this isn't the dark matter bit but the "before the Big Bang" bit, which this paper (I read the preprint as that article was awful) takes as a starting point.
The leading theory of the origin of the universe is the inflaton field. The idea is that this field is in a metastable state, i.e. in a state with a probability of spontaneously collapsing into a lower-energy state. The difference between the metastable energy and the "true vacuum" energy is the potential. Whatever this potential is must account for the energy of the universe, so is likely very high, higher perhaps than we can produce in particle accelerators.
Excitations of this field are the hypothesised inflaton particles responsible for the rapid expansion of the early universe before those unstable inflatons decayed to the sorts of matter we see today.
The author is deliberately not explicit about whether he thinks dark matter itself was created before the big bang (e.g. is itself an excitation of the inflaton field or another pre-bang field) or was "sourced" from such a thing. The latter seems the simplest and most sensible. The early universe is supposed to have been teeming with inflatons of energy outside or at the limits of our technologies, which then decayed to lighter particles, which may then have decayed to yet lighter particles, and so on.
In this instance, dark matter would be presumed to be extremely heavy and stable matter terminating a decay chain which is itself extremely high-energy. Dark matter as a direct product of inflaton decay would fit this picture. But to stress: inflaton creation was the Big Bang itself.
Dark matter is supposed to make up 80% of massive matter in order to explain the rotational velocity of galaxies. As accurate mass estimates for galaxies are on-going (e.g. only recently have we realised the abundance of supermassive black holes), it's worth treating with some scepticism. Dark matter is, sceptically, an error between current cosmological estimates of mass and current astronomical measurements of mass.
:up:
Don’t we now have direct confirmation of dark matter as a stuff in the universe (WIMPs specifically) from the Bullet Cluster observation?
It's not direct evidence, no, but it is a +1 for astronomical estimates of masses, i.e. the gravitational lensing is not consistent with heavier-than-expected galaxies. It also suggests that dark matter is not a very light WIMP like a neutrino.
Correction to above. I'm not doing good posting today.
I appreciate there was nothing in this to justify my earlier suggestion of caution.
The rotational velocities of galaxies suggest that the total mass at these distances is higher than the diminished luminosity would suggest, i.e. the distribution of density with increasing radius is not falling off correctly.
The bullet cluster and others appear to have centres of masses not coincident with the centre of luminous mass, again suggesting that the true mass is concentrated in a different way.
Fundamentally then dark matter is the difference between cosmological predictions and astronomical observations, both fields being ones where changes of knowledge are rapid. (It wasn't that long ago that we discovered that the universe is expanding at an increasing rate, and that black holes not only exist but are abundant.)
There are lots of candidate particles: it may be none, one or several of them, so long as they are gravitational and weakly electromagnetic (dark).
Modified gravity theories note and encode the relationships between baryonic (visible) mass distributions and the purported dark matter distributions necessary to explain the former's velocities. (These theories are like the social psychologists of cosmology: their raison d'etre is sound, but their MO is to claim every DM victory for themselves.) These relationships aren't explicable in DM terms because DM is not that well defined. They are more explicable in modified gravity terms, though.
That's not to say particular modified gravity theories are any more believable, but they do allow for the possibility that cosmological models of the future may yield different results from today, something that can be expected in rapidly changing fields. A general class of modified gravity theories is scalar gravity theories that predict a new gravitational field that would impact lensing observations. Such a field is present in the leading modified gravity theory which was shown to be consistent with the bullet cluster observations when one takes into account the three distinct centres of mass of the binary cluster system. That is, it states that the very relationship between baryonic and purported dark matter in rotational velocity observations is what knocks off the centre of mass in a three-mass system (the third mass being the mass of gas ripped from one cluster by another).
You are confusing dark matter with dark energy.
I don't follow links.
Cosmologists, like any other scientist, build theoretical models to test against empirical evidence. If your point is that they do not know in advance that the model is the correct one, then yes, you have correctly distinguished science (which proceeds from not knowing but wanting to find out) from religion (which proceeds from pretending to know and fearing being found out).
Nice turn of phrase!
Thats a common theme on most forums such as this by religionists and non-religionists. If scientists have problems understanding everything then so do most people on forums like this.
Puking out information from a popular physics book doesn't make us experts.
I'm sure you are aware to the concept that when one question is answered that 10 more questions pop up in its place (a common proverb). Missing one small detail in a concept can throw off the proper conclusion for that concept. This is similar to if we have an equation missing one variable and one coefficient for example. The whole output of the equation or function can change drastically.
This is a justification for considering science a work of fiction? Or, to put it another way, how does this relate to what you quoted?
You seem to be taking not knowing something as being seen as inferior. But you just quoted me as saying not knowing is the starting point.
Welcome to the forum by the way :)
Thanks for your welcome. No sarcasm intended. Basically i'm saying some people know more than others however there is no end in sight of Scientists still having major discoveries of how the Universe operates and also things that relate to 10 dimensions and beyond. Like i said if we get one variable or coefficient wrong it can change our whole view of reality.
Yes, you're right and, as I said, all scientists do is model reality with empirically-verified theory. So while it's right to say our whole "view of reality" (i.e. theoretical model of it) can massively change, the change in what it predicts (phenomena) have to be extremely restricted to match prior observations. The universe may behave as if it has precisely 11 dimensions, say. It might have 111. It might only have 4 or 5. But it behaves like it has 11.
Likewise it behaves as if there's dark matter and dark energy in a universe and otherwise follows current cosmological models. And it will behave differently in future cosmological models. More dark matter, less, none, dark matter made of one thing, dark matter made of fudge. As I said before:
Quoting Kenosha Kid
probably true. I'm about high school calculus level so i guess your right.
https://releases.jhu.edu/2019/08/08/dark-matter-may-be-older-than-the-big-bang-study-suggests/
https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.123.061302
(as Pfhorrest already noted, this is less of a shocking result than it may seem since the "Big Bang" in this context is the post-inflationary period in the inflationary model, not the hypothetical "t=0" spacetime singularity of non-inflationary big bang cosmology often referred to as "the big bang")
thanks i'll add it to my journal.
Have you a specific reference to that meaning of the universe? I know that Lawrence Krauss says that the universe "came from nothing," meaning in a technical sense that it spontaneously big banged out of the fluctuating quantum fields. He was certainly using universe in the sense I did: whatever happened after the big bang.
Other than Penrose's cyclic conformal cosmology, there is an endless succession of universes But even then, a universe is what happens between successive big bangs.
I'd like to see a reference to the definition of the universe as something that includes the big bang plus something else, other than Penrose's theory. This would be new to me.
Secondly, do you have a reference for any physicist claiming (while doing physics, not metaphysical speculation) that the universe is infinite in duration? Did it have a beginning or is there an infinite regress? Perhaps it goes back as 1/2, 1/4, 1/8, etc., so that although there's an infinite regress yet there is also a greatest lower bound.
Since I don't believe there are any physics grants going to postdocs to investigate these questions, I must -- at the risk of appearing overly blunt -- call bullpucky on each of your two claims that (1) the word universe commonly or standardly or even occasionally means something other than whatever happened after the big bang or the most recent big bang; and (2) that anyone seriously claims the universe is infinite either in the past or the future.
If you have references I'd be glad for the education.
ps -- The Wiki page on eternal inflation contradicts your claim about an infinite past.
"Alan Guth's 2007 paper, "Eternal inflation and its implications",[3] states that under reasonable assumptions "Although inflation is generically eternal into the future, it is not eternal into the past."" My emphasis.
https://en.wikipedia.org/wiki/Eternal_inflation
Quoting Enai De A Lukal
Some inflationary models do still posit a singularity at the beginning of time, in which case the universe had a beginning just as in ordinary non-inflationary big bang models. But there is also a model of eternal inflation, where there wasn't necessarily any start of time, just a local stop of inflation, which is the "big bang" for all intents and purposes as we usually mean it, in such a model. It seems to be in that context of eternal inflation specifically that the term "big bang" is used that way, rather than to mean a singularity.
You can start here for info on eternal inflation:
https://en.wikipedia.org/wiki/Eternal_inflation
The YouTube channel PBS Space Time also has a great series of five video about it, full playlist here:
https://www.youtube.com/playlist?list=PLsPUh22kYmNCc3WCKb5yF136QSRf0xErm
But I think these are probably the two that are most relevant:
[video]https://www.youtube.com/watch?v=xJCX2NlhdTc&list=PLsPUh22kYmNCc3WCKb5yF136QSRf0xErm&index=5[/video]
[video]https://www.youtube.com/watch?v=chsLw2siRW0&list=PLsPUh22kYmNCc3WCKb5yF136QSRf0xErm&index=6&t=0s[/video]
Yes thank you. I haven't read it all yet so perhaps this point is explained. In the little bit that I read, they said that Guth said that time goes infinitely forward but not necessarily backward. And I thought that was inconsistent with what you are saying. But perhaps there are infinitely backward models too. In which case they must be metaphysical speculation rather than actual physics, because there is no theory of actual infinity in the physical world, universe or multiverse. You might as well invoke turtles all the way down as an "infinity of time into the past" in this context. There's no scientific meaning to the phrase.
ps -- My argument rules out forward infinity too as being a physical theory, rather than metaphysical speculation more suitable for the pub than the seminar. Physics has no actual infinity, period. The modern theory of infinite sets does not refer to the physical world. I believe I've even made this very point to @Metaphysician Undercover once or twice. Mathematics does not necessarily refer to the real world; and in this instance -- pending some development yet to be made -- it does not.
So just to be clear, I don't object to going backward or forward; but positing an actual infinity of time in either direction is simply non-physical. It is a metaphysical assumption. It is by definition outside the realm of science.
Science aside, I don't get the philosophical objection to the possibility of an "actual infinity". As far as we can tell, the universe is consistent with the possibility of it being infinite in spatial extent: it is, at the very least, so big that our current measurements can't distinguish between how big it is and it being infinitely big. Can you elaborate on what would be wrong with supposing that it might be infinitely big (or that it might be infinitely old, etc)?
I think the confusion is between the inflation of the universe, which is described above as being eternal into the future but not the past, i.e. the universe had a start but will have no end, and the eternal inflation field which may have caused the start of this universe, which may be eternal into the past, and may or may not be eternal into the future depending on whether it fully and universally collapsed into the vacuum of our universe. Multiverse theory says it did not do so, and continued making new universes before and after ours through quantum superposition and/or local collapse.
There is also a sense in which eternal inflation fields are timeless. They expand into any dimension, but after expansion remain the same as before, e.g. [math]V(x_1, t_1) -> V(x_2, t_2) = V[/math].
I've worded this imprecisely. In eternal inflation theory, it's still the same field, just in two different states. These states can coexist either as spatial separations or quantum superpositions (mathematically equivalent).
See the works of Sean Carroll & Jennifer Chen, and particularly Anthony Aguirre & Steven Gratton.
You'll have to provide a link for the absurd (and false) claim that there is a reputable theory of physics positing an infinite past.
I have no philosophical objection. The claim made by you was that science posits an infinite past, which is false. If we're not doing science, you can say anything you like since it's unprovable and unfalsifiable. I'm challenging you on your claim that there's a scientific theory positing an infinite past. I challenged you to provide a link. You linked a Wiki article that directly contradicts your claim. When I noted that, you linked the same Wiki article again. And now you say you're NOT talking about science but rather philosophy,
This is the third time you've linked the same article which directly contradicts your claim.
Quoting Pfhorrest
Quoting Pfhorrest
You seemed to think that it would be absurd to even think that it could be infinitely old, and I don't see why that or any other "actual infinity" would be absurd.
ETA: Also, Kenosha wrote:
Quoting Kenosha Kid
Nobody is claiming anything in science says the past is definitely infinite, just that it's not definitely finite (which, NB, is not the same thing as "definitely not finite").
A rather histrionic request, but okay. Susskind is the obvious, such as in:
https://arxiv.org/abs/1204.5385
You can check Guth's 2007 review where he also discusses inflation fields that are past eternal but bounded.
If they're bounded then I already acknowledged that example as in 1/2, 1/4, 1/8, ... in which there's no "first step" but is nonetheless bounded below. This surely isn't what the other poster, I think it was @Pfhorrest, meant by infinite past.
"Past eternal but not bounded?" Sorry that doesn't make a lot of sense.
I'll read Susskind's paper and I appreciate the reference to a physicist I take seriously.
I'm willing to stipulate that Susskind and others (Penrose for sure) have theories positing and endless sequence of universes before the big bang.
I don't think it's absurd at all.
I do think that you haven't backed up your claim that there's a scientific theory to that effect, other than Penrose's. If my knowledge of the literature is insufficient, @Kenosha Kid has pointed me to a paper of Susskind which I'm looking forward to reading, since I know Susskind is a serious physicist.
I'm still confused by where you're coming from. Sometimes you claim an infinite past is a plausible or at least published scientific theory; but recently you said that you aren't talking about science, only philosophy.
For my part I never imagine I'm wise enough to have an opinion on when the world started or how. I'm only discussing the state of the art of science. If there's more speculation about an infinite past than I've been formerly aware of, then I'll stand corrected on this point. But please be clear. I'm not arguing against an infinite past, an infinite future, or an infinite number of turtles all the way down.
I'm arguing against the claim that an infinite past is a serious scientific theory. I'll know more after I read the Susskind paper.
Big crunch sequence? Rather ruled out by the evidence.
Quoting fishfry
It makes as much sense as an infinite but bounded universe, which is hardly a foreign idea in cosmology.
Rather than my spouting off more, I'm going to read the Susskind paper because he's someone I respect AND he's not Penrose so his ideas would be more mainstream. I'm not really up on what the speculative cosmologists do these days.
I will say that mathematically I'm troubled by the casual use of infinity in speculative physics. My understanding is that when physicists say infinity, they generally do not mean what mathematicians regard as infinity. If someone thinks there are infinitely many "instants" in time, are there countably many or uncountably many? Is the continuum hypothesis true or false about these infinitely many instants? Or if time is infinite in one direction or the other, what exactly does that mean if there aren't infinitely many instants. Are there infinitely many Planck times, or what exatly?
I don't think physicists think clearly about infinity otherwise they'd ask themselves these questions. In mathematics to get the theory of infinity off the ground we must assume a powerful axiom call the axiom of infinity; and there is no evidence that the axiom of infinity is true about the physical world.
So I do have a lot of misgivings whenever I hear physicists talking about infinity. And when I take the trouble to dig deeper into the details, I generally find that they're not using the word the same way mathematicians do.
But these are just impressions, and as I say I don't know much about speculative cosmology.
Yep. Despite poor Mr. Fishfry's dogmatic (and largely baseless) insistence to the contrary, the question of the past duration of the universe is an open one, with "serious" models of both varieties. On the eternal side, it sounds like someone has mentioned Penrose's cyclical cosmology in addition to eternal inflation, and loop quantum cosmology also posits a cyclical universe that is past-eternal/infinite as well. Its a shame neither science nor reality is especially obliged to honor our metaphysical prejudices, but it seems some handle this fact better than others.
But you just said a moment ago:
Quoting fishfry
Quoting fishfry
I said there are scientific theories that don’t rule it out. That doesn’t mean they say it is definite so.
I'm going to stop posting in this thread till I read the Susskind paper. But again, if by "it" you mean a physical theory that incorporates infinity, then my earlier remarks would have to apply. Namely, that I suspect that the physicists are using the word infinity in a manner inconsistent with how mathematicians think of infinity. But in philosophical discussions, the physics infinity acquires the trappings of respectability of mathematical infinity over the past 140 years. This I believe is a logic trap. We must remember that when physicists talk about infinity, they generally have no idea what they're talking about mathematically. Just like with everything else they do. Physicists use math, they don't do math; and one should not rely on physicists for the logically correct foundations of things.
Even well-accepted cosmological theory is future eternal. That's not speculative, it's consistent with empirical evidence.
And if we're talking infinities, it is also consistent with a good body of empirical evidence that the universe is geometrically flat and thus (spatially) infinite. Once again, nature/reality not overly interested in our metaphysical prejudices- if it wants to be infinite, that's what its going to be and we can either get hip with it or gtfo.
I'm certainly not saying your wrong. When people say the universe is flat, does that imply it has a center or that it curves around itself and there is no center. I actually tried to look this up but couldn't find an answer, atleast not as of yet. Does that also imply if you head in one direction in the universe you'll end up back at the same spot or does that imply the opposite?
So if the universe had positive curvature, it would be like a sphere- spatially finite/bounded, if you traveled far enough you'd eventually end up back where you started. But if the universe has either zero curvature (flat) or negative curvature (hyperbolic, so like a saddle), it would be spatially infinite- you could travel indefinitely far and would never return to where you started. So far as our best measurements go, the universe appears to be geometrically flat- so spatially infinite.
In a spatially infinite universe, would there be a center of the universe?
On a saddle an ant could travel all the way around the saddle and come back to the same spot. Are we sure the scientific method has been used to prove some of this stuff to show the shape of the universe? We are both aware that if you have a long equation with many variables, coefficients and constants, if just one variable is missing it can throw off the whole equation. I suppose it would be an act of faith for us to assume that in 10 years future Scientists will by and large agree with modern scientists.
^ Modern physics in a nutshell.
"like" a saddle, not a literal, actual saddle- a hyperbolic surface, an infinite saddle: a universe with negative curvature doesn't curve back on itself like one with positive curvature- its "curving" in the wrong direction, and so is open, unbounded, infinite in extent.
And as always, the best we can say is that the current state of the evidence supports this- science is fallible and we are not psychics or soothsayers, so its always possible future evidence contradicts or even overturns our current understanding. But I would submit that rejecting something on the mere possibility that it may, someday, turn out to be false, is not rational.