brown dwarfs negate big bang theory?

[eisenfaust2009]

I watched this video

 

http://www.youtube.com/watch?v=X4rv9BqTWzI&NR=1

 

and below in the comments one guy said that Brown dwarf stars take a lot longer than 14B years to move through the Main Sequence!

 

Is this true? Im only basic about cosmology because i am a business student.

Please explain simply and non-biased(non religious people making pseudo scientific claims to make me lose trust in science)

 

I really think that big bang theory is true. please tell me its true...

 

sigh, i dont wanna lose faith in science even if its empirical

 

i searched up brown dwarfs and big bang in google and it came up with

 

this!!!!!! are u kidding me?

plz explain

 

 

!

Moderator Note

copyrighted material edited. If you want to present this, please provide a link to the specific material (not advertising links, like to book publishers). You can quote small parts, but not whole sections.

Edited April 1, 2011 by swansont
copyright

[Airbrush]

Nice You Tube, thanks for that. It is about "dark flow" so I don't know what "brown dwarfs negate..." has to do with that?

 

Is dark flow something outside our Big Bang? That model seems like another Big Bang is bumping up against the edge of our Big Bang.

 

From Wiki:

 

"Dark flow is a term from astrophysics describing a peculiar velocity of galaxy clusters. The actual measured velocity is the sum of the velocity predicted by Hubble's Law plus a small and unexplained (or dark) velocity flowing in a common direction.

 

According to standard cosmological models, the motion of galaxy clusters with respect to the cosmic microwave background should be randomly distributed in all directions. However, analyzing the three-year WMAP data using the kinematic Sunyaev-Zel'dovich effect, the authors of the study found evidence of a "surprisingly coherent" 600–1000 km/s flow of clusters toward a 20-degree patch of sky between the constellations of Centaurus and Vela.

 

The authors (Alexander Kashlinsky, etc) suggest that the motion may be a remnant of the influence of no-longer-visible regions of the universe prior to inflation. Telescopes cannot see events earlier than about 380,000 years after the big bang, when the universe became transparent (the Cosmic Microwave Background); this corresponds to the particle horizon at a distance of about 46 billion (4.6×1010) light years. Since the matter causing the net motion in this proposal is outside this range, it would in a certain sense be outside our visible universe; however, it would still be in our past light cone...."

 

That seems interesting. How else can something "outside our visible universe" still be in our past light cone?

 

The Great Attractor however, is more localized, between 150 and 250 Million light years away. And even the Great Attractor is getting pulled in the direction of dark flow.

 

Suggestion to moderators, perhaps rename this post with a descriptive title, like "Dark Flow"?

[michel123456]

Very interesting indeed.

 

 

That seems interesting. How else can something "outside our visible universe" still be in our past light cone?

 

Here I am again: Moderators, be prepared!

 

Your own past (10 minutes ago) lies inside your past cone, right?

Question:

Is your past a part of your visible universe?

[imatfaal]

trying to answer airbrush's question;it is that visible universe is usually thought of as that portion of the universe which could be observed using EMR-detection - and we can detect/observe nothing during or before the universal opacity of the era of last scattering which finished around 380-400k years after BB. There is clearly a part of the universe that is within our past light cone earlier than 380000 years post big bang - otherwise where did we come from - and that part of the universe will never be visible using EMR-detection. The observable universe is time-limited because of the era of last scattering - the past light cone is not. When/if we can use neutrinos or gravitational waves to probe the very ancient universe (ie detection methods that are not blocked by the opaqueness of the universe then) the observable universe will increase in magnitude

[eisenfaust2009]

you nuts, read my post carefully. the video content is irrelevant. go look down at the comments section who says that "the universe is annoying as him". he says big bang does not work with brown dwarfs. READ HIS COMMENT plz

 

because the main sequence is greater than 14b yrs and univ is only 13.7b yrs old

[michel123456]

The video has been removed from Youtube, no comment available either.

[insane_alien]

because the main sequence is greater than 14b yrs and univ is only 13.7b yrs old

 

So?

 

not that you can really define a main sequence for brown dwarfs as there isn't a whole lot of fusion going on.

 

but, I'm no astrophysicist, so maybe there is an equivalent.

 

If the main sequence DOES take longer than the life of the universe than all this says is that we should't observe any dead brown dwarfs. they should all be either forming orformed and burning along merrily.

 

Funnily enough, this is what we've seen so far.

 

an equivalent to what you are saying is " humans have an average lifespan of 80. the fact that there have been people born this millenium and it isn't 2080 invalidate birth"

[Spyman]

I watched this video

 

...youtube.com...

 

and below in the comments one guy said that Brown dwarf stars take a lot longer than 14B years to move through the Main Sequence!

 

Is this true?

First I must say that no one should put even the slightest of trust in any random comments on youtube.

 

But it is true that Brown Dwarfs have a much longer lifetime than ordinary stars, however they are already formed as Brown Dwarfs from birth.

 

The fact that they are predestined to have a much longer progress through their stellar evolution than how long the Universe has existed so far, does not negate the Big Bang theory.

(Unless we discover several that evidently are much older than 14 billion years, but so far none older have been observed.)

[eisenfaust2009]

http://www.mail-archive.com/epistemology@googlegroups.com/msg00590.html

 

Read this and tell me if this is true. I have no idea obviously.

[ZEkeyon]

Greetings,

 

That is a fascinating article. The presentation seems fairly legitimate. The article cites scientists who are making certain claims and drawing conclusions from the recent developments and discoveries. However, nowhere in the article (as far as I can see) does it suggest that the existence of these brown dwarfs contradicts the Big Bang Theory. As it was mentioned before, there would have do be an observation of a brown dwarf in a state of its lifetime exceeding the current age of the universe.

 

I would like to address a concern I have with the OP, although this may not be directly related to cosmology. In regards to the comment that you expressed your fear of losing faith in science. Quite the contrary, science is based upon reason (including reasonable assumptions). Theories like the current cosmogonical model of the Big Bang are based upon our current understanding of nature as well as the results of our observations of the universe. The very fact that falsifiable claims (based upon this model) can be made as to what to expect when observing the universe demonstrates the true value of the scientific method. It is inevitable that as our understanding broadens and technology improves the cosmogonical model will need to be modified to better fit our observations.

[Spyman]

I skimmed the Article briefly, it don't have any explanation of why a huge number of discovered Red and Brown Dwarfs would negate the Big Bang theory and clearly admitt that it would be very hard to observe a Black Dwarf even if they should exist.

 

The Article did NOT bring up any evidence whatsoever that we have observed a stellar object older than the estimated age of the Universe.

 

This is what Wikipedia says of Black Dwarfs:

 

"A black dwarf is a hypothetical stellar remnant, created when a white dwarf becomes sufficiently cool to no longer emit significant heat or light. Since the time required for a white dwarf to reach this state is calculated to be longer than the current age of the universe of 13.7 billion years, no black dwarfs are expected to exist in the universe yet, and the temperature of the coolest white dwarfs is one observational limit on the age of the universe."

http://en.wikipedia.org/wiki/Black_dwarf

 

I will repeat the last part of the quote once more to make it absolutely clear:

 

The temperature of the coolest White Dwarfs is one observational limit on the age of the universe.

 

 

Conclusion: A huge number of discovered Red and Brown Dwarfs does NOT negate the Big Bang theory, since none of them are older than ~14 billion years.

[MigL]

Star's lifetimes are inversely proportional to their temperatures. The hot ones live fast and die young ( just like people ). Blue giants have lifespans of 100s of million years. Our sun has a lifespan of 10 billion years. The much slower burning brown dwarfs ( Jupiter is an order of size magnitude removed from being a brown dwarf ) have even longer lifetimes, BUT no data indicates they are older than 13 billion years.

[gabl8a89]

according to what I know, brown dwarf dont have "main sequences" because they dont fuse Hydrogen

and just fuse Helium or Lithium, but how long can a brown dwarf lives?

[Spyman]

Many Brown Dwarfs are not hot enough to fuse even Deuterium and without or after nuclear burning they will remain intact and slowly cool down.

 

In addition, many brown dwarfs undergo no fusion; those at the low end of the mass range (under 13 Jupiter masses) are never hot enough to fuse even deuterium, and even those at the high end of the mass range (over 60 Jupiter masses) cool quickly enough that they no longer undergo fusion after a period of time on the order of 10 million years.

http://en.wikipedia.org/wiki/Brown_dwarf#Distinguishing_low-mass_brown_dwarfs_from_high-mass_planets

[Widdekind]

Some galaxy cluster, half-way between 'here' and 'the great attractor' -- which lies outside our past light cone -- has a different visible universe, than we do. So, that 'great attractor' might be in those galaxies' past light cones, able to exert gravitational influences on them, which we then witness. Is our local group part of that 'dark flow' ? If so, then 'something strange' has happened, such that earth is being affected, by causally a-connected events.

[Spyman]

Widdekind, I don't understand what you are trying to say...

 

First, the Great Attractor is not outside of our past lightcone, we can see it and are pulled towards it.

 

Secondly, there are likely galaxies located so that can see us but not the Great Attractor and to them we are pulled towards something they can't see, but I don't understand the "strangeness" of that view.

 

Lastly, I don't see the relevance of your post to the age of Brown Dwarfs versus the Big Bang theory.

Edited May 24, 2011 by Spyman

[Widdekind]

Widdekind, I don't understand what you are trying to say...

 

First, the Great Attractor is not outside of our past lightcone, we can see it and are pulled towards it.

 

Secondly, there are likely galaxies located so that can see us but not the Great Attractor and to them we are pulled towards something they can't see, but I don't understand the "strangeness" of that view.

 

Lastly, I don't see the relevance of your post to the age of Brown Dwarfs versus the Big Bang theory.

 

I did not realize, that 'The Great Attractor', is distinct from "The Dark Flow Attractor". The former resides well within our Visible Universe, whilst the latter may not. As for every observer having a unique vantage point of observation, and hence VU, so that every observer would witness far-off matter which was affected by phenomena yet-even-farther away, we are saying the same thing. Such seems normal, not extra-ordinary. The 'Dark Flow' seems to be a coherent flow, of everything within our own VU. If so, perhaps that few x 10^-3 c flow represents an actual initial condition, of the Big Bang ??

 

Brown Dwarfs do not negate the Big Bang theory. They are predicted to live ultra-long-lives, and none have yet been seen to violate predictions. Rather, they simply haven't aged much. If there were ~10² super-Jupiter-sized Brown Dwarfs, per solar-mass star, that could account for DM, yes ??

[Spyman]

Brown Dwarfs do not negate the Big Bang theory. They are predicted to live ultra-long-lives, and none have yet been seen to violate predictions. Rather, they simply haven't aged much.

Yes, that is correct, but you didn't explain why speculations of Dark Flow or Dark Matter belongs in this thread.

 

Dark Flow is not confirmed and even so those claimed measurements only reach ~3 billion lightyears out.

 

Dark Matter is not likely undetected Brown Dwarfs, since we observe an otherwise impossible abundance of Deuterium.

[Widdekind]

Dark Matter is not likely undetected Brown Dwarfs, since we observe an otherwise impossible abundance of Deuterium.

 

Or, some symbol is wrong, in the chalk, on the blackboard. Can you confirm, that calculations of Primordial Nucleosynthesis, account for the ultra-high 'redshift effect', of the then ultra-fast space-time expansion? Even high-temperature plasma, when being spread out away from itself at ultra-high rates, might not manifest as much fusion, as it would, in a static spacetime. And, at least the original ABG paper(s) seemingly assumed a flat space-time... how would closed curvatures, and/or cosmological constants, effect the physics? In one ABG 1948 paper, those authors assumed that PNS fusion occurred in the matter-dominated era, when it would have been well within the radiation-dominated era, when the scale-factor grew as t^1/2, not t^2/3. It is a huge leap, from terrestrial chalk boards, to hundreds of thousands of cubic giga-light-years, of actually existing space-time... which must then be retro-dicted back through the Matter-Radiation transition, to super-early eras...

Edited May 25, 2011 by Widdekind

[Spyman]

Or, some symbol is wrong, in the chalk, on the blackboard. Can you confirm ... bla. bla. bla. (speculations) bla. bla. bla. ...

No, if you want to challenge already accepted scientific consensus then the burden of proof is upon you.

 

And for the third time: Why are you twisting this thread off-topic?

 

Speculations on the nature of Dark Matter does NOT belong in the context here!

[Widdekind]

No, if you want to challenge already accepted scientific consensus then the burden of proof is upon you.

 

And for the third time: Why are you twisting this thread off-topic?

 

Speculations on the nature of Dark Matter does NOT belong in the context here!

 

Please read the ABG 1948 paper, they errantly assumed that PNS would occur in the matter dominated era. Can you cite a more modern source, detailing the mathematics of the same? I have several introductory Astrophysics books, but none delve down into the details at all.

[Spyman]

Please read the ABG 1948 paper, they errantly assumed that PNS would occur in the matter dominated era. Can you cite a more modern source, detailing the mathematics of the same? I have several introductory Astrophysics books, but none delve down into the details at all.

Please read the ScienceForums.Net Forum Rules, especially:

 

5. Stay on topic. Posts should be relevant to the discussion at hand. This means that you shouldn't use scientific threads to advertise your own personal theory, or post only to incite a hostile argument.

 

and:

 

10. Keep alternative science and your own personal conjecture to the appropriate forum (Speculations). Threads in the ordinary science forums should be answered with ordinary science, not your own personal hypothesis. Posting pet "theories" in mainstream science forums is considered thread hijacking.