The main lesson of thermodynamics


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The main lesson of thermodynamics  ---   the tax nature  charges us for getting anything useful done is entropy increase.  Wear and tear of the cosmos  is the necessary price we pay for getting anything done. Without entropy increase there would be no life. 

A Carnot Engine that works  at 100 percent efficiency produces no net mechanical work. So a totally efficient Carnot Engine  is  equivalent (in practical terms)  to no Carnot Engine at all.  

Perfect Efficiency cannot be achieved even in principle.

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2 hours ago, Brant Gaede said:

How did it increase decrease in the first place?

--Brant

Nobody knows that for sure.  It is assumed that at the time of the Big Bang  entropy was low and it is getting larger.  It can never decrease.  Or to put it in probablistic terms, as Boltzmann did,  the probability that total entropy of the cosmos  can decrease is so small  that the expected waiting time for such a happening would be the current age of the cosmos  multiplied by a very,  very large number.   Do not hold your breath while waiting for the second law of thermodynamics to be falsified.  If you do, you will turn blue and faint.

No one has ever done an experiment that has falsified the second law of thermodynamics.  Ever....  And many people have tried. 

Eddington and Einstein were convinced that the second law of thermodynamics is the closest thing to a sure bet that exists in physical science. So far no effect or process has ever been found to contradict their confidence.  It is interesting that  there biological processes of living things can be largely described in thermodynamic terms.   Life is because entropy increases.  Schrodinger gave a lecture and wrote a book relating biological processes and thermodynamics.

https://en.wikipedia.org/wiki/What_Is_Life%3F

"In the book, Schrödinger introduced the idea of an "aperiodic crystal" that contained genetic information in its configuration of covalent chemical bonds. In the 1950s, this idea stimulated enthusiasm for discovering the genetic molecule. Although the existence of DNA had been known since 1869, its role in reproduction and its helical shape were still unknown at the time of Schrödinger's lecture. In retrospect, Schrödinger's aperiodic crystal can be viewed as a well-reasoned theoretical prediction of what biologists should have been looking for during their search for genetic material. Both James D. Watson, and independently, Francis Crick, co-discoverers of the structure of DNA, credited Schrödinger's book with presenting an early theoretical description of how the storage of genetic information would work, and each respectively acknowledged the book as a source of inspiration for their initial researches"

https://en.wikipedia.org/wiki/Entropy_and_life

Claude Shannon in his ground breaking work on information theory  represented information as entropy

https://en.wikipedia.org/wiki/Entropy_(information_theory)

 

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33 minutes ago, Brant Gaede said:

It seems we can know only entropy and not the other side--if there be one--of the existence coin.

If existence is a spinning top, who/what started it spinning?

--Brant

Maybe it was always spinning.  The idea of a body  always  spinning at a constant angular velocity is consistent with rotational inertia.  The idea of a body moving in a straight line at constant velocity eternally is consistent with inertia.

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The idea is existence has always existed because non-existence cannot exist. It's a parasitical concept on existence.

But the begged question is whether that's epistemological (and the limitation of language--is it too binary?) or simply metaphysical?

--Brant

and maybe its not worth thinking about--the more we know the weirder reality gets, according to an astrophysicist

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9 hours ago, Brant Gaede said:

The idea is existence has always existed because non-existence cannot exist. It's a parasitical concept on existence.

But the begged question is whether that's epistemological (and the limitation of language--is it too binary?) or simply metaphysical?

--Brant

and maybe its not worth thinking about--the more we know the weirder reality gets, according to an astrophysicist

And he is right.   There is more in heaven and earth than can be trapped inside our philosophical constructs. As it as  all of our efforts in the physical sciences have given us good information on only 4 percent of the cosmos.  There is the 96 percent of which we know little or nothing. Fortunately the 4 per cent we know about is the part of the cosmos  that we need to know in order to survive and even flourish.  

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We know more than 4 percent of the universe and as evidence I submit the idea that since we have never seen the “laws of existence” change no matter where we have looked, then data and conjecture reliably tell us the universe is the same wherever it exists. Peter

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5 hours ago, Peter said:

We know more than 4 percent of the universe and as evidence I submit the idea that since we have never seen the “laws of existence” change no matter where we have looked, then data and conjecture reliably tell us the universe is the same wherever it exists. Peter

The laws of physics in a black hole are very little like the laws of physics outside the black hole. The "laws of existence"  are rules of logic.  They have little in common with physical laws.  We cannot really say for sure what the laws of physics  governing  (so-called)  dark matter are.  We don't know what it is made of. All we can say at this point is that it gravitates.  

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Perhaps the word law is inelegant. Still, we have seen existence which includes matter in and outside of a black hole, though technically we only infer what we see as an image of a black hole. I suppose any matter or light ejected as it "nearly" goes into a black hole doesn't count as having left a black hole. I saw a picture of two black holes circling each other. When they unite I imagine the earth my shake a bit from gravitational waves.  

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1 hour ago, Peter said:

Perhaps the word law is inelegant. Still, we have seen existence which includes matter in and outside of a black hole, though technically we only infer what we see as an image of a black hole. I suppose any matter or light ejected as it "nearly" goes into a black hole doesn't count as having left a black hole. I saw a picture of two black holes circling each other. When they unite I imagine the earth my shake a bit from gravitational waves.  

What  you see is the matter in the event horizon being crunched so hard it gives of strong electromagnetic radiation in the X-Ray and Gamma Ray spectrum.

And no matter or light is ejected from a black hole.  Whatever goes into a blackhole stays there and never comes out. 

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5 hours ago, BaalChatzaf said:

What  you see is the matter in the event horizon being crunched so hard it gives of strong electromagnetic radiation in the X-Ray and Gamma Ray spectrum.

And no matter or light is ejected from a black hole.  Whatever goes into a blackhole stays there and never comes out. 

Are black holes for real?

--Brant

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20 hours ago, BaalChatzaf said:

What  you see is the matter in the event horizon being crunched so hard it gives of strong electromagnetic radiation in the X-Ray and Gamma Ray spectrum.

And no matter or light is ejected from a black hole.  Whatever goes into a blackhole stays there and never comes out. 

Is “the big bang”, which resulted in the “big expansion” not affecting black holes? If there ever were a “big contraction” from gravity, resulting in another “big bang” it might mean the end of this existence. But so far I see no evidence for a universal “big contraction”. Well, not yet.

If humans or our ancestors survive infinitely in an expanding universe we may need to have the technology to collect expanses of matter the size of galaxies.  

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17 hours ago, Brant Gaede said:

Are black holes for real?

--Brant

Apparently so.  If something behaves like a black hole  it is a black hole. Very large Black Holes have been observed at the center of other large galaxies. 

When a large number of stars are seen orbiting around a central point that is not visible in various spectra  it is a very  large mass gravitating body that does not put out any light  or is an emitter of gamma rays  but not otherwise visible.  That is almost certainly a Black Hole.

If one sees a group of visible massive bodies in Keplerian orbits around a point at which nothing is visible one can calculate the mass of the body around which the other massive bodies are orbiting.  A large mass indicates a Black Hole.  That is how we spot Black Holes in other galaxies and our own.  There is a Black Hole at the center of the Milky Way.   

Have a look see here:  https://en.wikipedia.org/wiki/Supermassive_black_hole

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2 hours ago, Peter said:

Is “the big bang”, which resulted in the “big expansion” not affecting black holes? If there ever were a “big contraction” from gravity, resulting in another “big bang” it might mean the end of this existence. But so far I see no evidence for a universal “big contraction”. Well, not yet.

If humans or our ancestors survive infinitely in an expanding universe we may need to have the technology to collect expanses of matter the size of galaxies.  

The cosmos seems to be expanding at an ever accelerating rate.  There will be no Big Crunch apparently.  

See: https://en.wikipedia.org/wiki/Accelerating_expansion_of_the_universe

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14 minutes ago, BaalChatzaf said:

The cosmos seems to be expanding at an ever accelerating rate.  There will be no Big Crunch apparently.  

See: https://en.wikipedia.org/wiki/Accelerating_expansion_of_the_universe

From Wikipedia: The accelerating expansion of the universe is the observation that the universe appears to be expanding at an increasing rate, so that the velocity at which a distant galaxy is receding from the observer is continuously increasing with time. end quote

ET go home. ET never come back, Eliot. Sigh. The universe expanding and ET’s home is further away from earth with each passing day.

I wonder if the rate of expansion of matter is accelerating the further from the original Big Bang it gets? Since matter is in infinite locations, some matter is obviously moving slower from the obvious gravitational pull but perhaps also from the pull of *time,* and distance from the highest concentration of mass. This may make it less likely we will ever meet an alien.

Last Gasp Larry (say it three times.)    

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1 minute ago, Peter said:

From Wikipedia: The accelerating expansion of the universe is the observation that the universe appears to be expanding at an increasing rate, so that the velocity at which a distant galaxy is receding from the observer is continuously increasing with time. end quote

ET go home. ET never come back, Eliot. Sigh. The universe expanding and ET’s home is further away from earth with each passing day.

I wonder if the rate of expansion of matter is accelerating the further from the original Big Bang it gets? Since matter is in infinite locations, some matter is obviously moving slower from the obvious gravitational pull but perhaps also from the pull of *time,* and distance from the highest concentration of mass. This may make it less likely we will ever meet an alien.

Last Gasp Larry (say it three times.)    

We know nothing of the Cosmos beyond the observable horizon.  Space, past that point, is expanding faster than light speed (yes, space is allowed to expand as fast as it pleases).  So we will never know what, if anything,  is beyond the light speed horizon.  Sometime in the distant future the only observable stars will be in our own galaxy.  I find the thought depressing.  Right now we cannot see any more than 46 billion light years distant. Which is to say the light from anything now beyond 46 billion light years will never reach is no matter how long we wait.  

Enjoy the sights of the cosmos while you still can. 

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With the advance of artificial human perception I think we will see a shimmering oasis out there, or a lemonade stand. So much is still to come I can't feel depressed. WE have learned more in the last five years than we learned in the previous . . .   

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3 hours ago, Peter said:

With the advance of artificial human perception I think we will see a shimmering oasis out there, or a lemonade stand. So much is still to come I can't feel depressed. WE have learned more in the last five years than we learned in the previous . . .   

We can't "see"  anything other than with received electromagnetic radiation  or by gravitational interaction.  When the nearest thing to us is far enough a way so that the space between us and it  is expanding faster than the speed of light  we shall not see that thing  either electromagnetically or gravitationally.  Information cannot travel faster than the speed of light. 

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Information cannot travel faster than the speed of light? Yet the universe can expand faster than the speed of light? I know the concept of "wormholes" is scientifically controversial and a literary device too, but Horatio, what is not known in your philosophy? 

If earth is expanding with the universe in one direction, couldn't we broadcast backwards and get the information there at faster than light speeds if the receiver of the message is also behind us but speeding in the same direction? Make sense?   

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2 hours ago, Peter said:

Information cannot travel faster than the speed of light? Yet the universe can expand faster than the speed of light? I know the concept of "wormholes" is scientifically controversial and a literary device too, but Horatio, what is not known in your philosophy? 

If earth is expanding with the universe in one direction, couldn't we broadcast backwards and get the information there at faster than light speeds if the receiver of the message is also behind us but speeding in the same direction? Make sense?   

It is space that is expanding, not matter.

There does not seem to be any known upper bound on how fast space can expand (either in theory or apparently in fact).  On the other hand information is carried by bosons.  Bosons  are the particles (with integral spin) which mediate all four known reactions. So far no one has observed the graviton which mediates gravitational interaction so it remains hypothetical, but any quantum gravitation will require it.  The graviton, if it exists, is a spin 2 boson.

See:  http://www.hep.ucl.ac.uk/~jpc/all/ulthesis/node11.html

Two teams  discovered that the cosmos is not only expanding  but that the expansion is accelerating.  Eventually, far enough away, the cosmos is expanding at greater than light speed  so any light the comes from those parts cannot reach us. 

Please see: https://en.wikipedia.org/wiki/Accelerating_expansion_of_the_universe

 

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From: Christopher A Robinson To: objectivism Subject: OWL: Big Bang Date: Wed, 16 Feb 2005 22:34:49 -0600

Dear all, I have been listening to David Harriman's lectures on the corruption of the philosophy of physics, and in one section a questioner calls the Big Bang theory "pseudoscience." I could not tell for sure, but it seemed that Harriman agrees with this assessment.

 

Is this the case, have Objectivist physicists come out against this idea? If so, why?

Christopher Robinson

 

From: "Ralph Blanchette" To: "OWL" Subject: OWL: Re: Big Bang Date: Thu, 17 Feb 2005 17:45:57 -0500

I can't answer Christopher's question but I would welcome a review which summarizes Harriman's main arguments.  The ARI "oral tradition" of objectivist espousal may be an excellent means of earning revenue in large multiples of what one might earn from a book (based on a likely price/demand curve -- and I am not implying that this is necessarily a bad idea) but it does require deep pockets to keep up with the ongoing work. It also precludes skimming for information and the normal give and take of scholarly review.

 

I can tell you that I think modern physics is somewhat shaky in the "philosophical foundations" department, leaning heavily on positivist and Kantian notions that require no clear and certain connection between what are known as "sense (or observational or experimental) data" (as opposed to perceived entities) and any intelligible reality. Objectivism has little to say about the subjects of science per se, but insists in its axioms on the non-contradictory identification of entities by a consciousness that is in direct touch with a knowable reality, i.e., a reality that can be known by building up a sound _conceptual structure_ through observation and inductive reasoning. Of course one need not be an "Objectivist physicist" to reject the epistemological agnosticism implied by Kant's distinction of the "phenomenal" and the "noumenal" that underlies much of this kind of thought. On the bright side, few, if any, physicists would insist that it is only "social convention" that explains the phenomenal world, as do our postmodernist "thinkers". Does Harriman deal with these issues in detail?  What "corruptions" does _he_ find?

--Ralph

 

From: "John Drake" To: <objectivism Subject: OWL: RE: Big Bang Date: Thu, 17 Feb 2005 15:38:39 -0800. While I have never heard David Harrimans' lectures, there is an undercurrent of physicists that question whether there exists such a thing as the Big Bang.  Eric Lerner wrote a book entitled "The Big Bang Never Happened", where he postulates that much of astronomy is based on the flawed reasoning that gravity is the major force governing the universe rather than the more powerful electro-magnetic forces.  Lerner instead argues that what we are observing today, the expansion of the "known" universe, can be better described as a local effect caused by these electro-magnetic forces.  It's been several years since I read this book, so my knowledge of the details are sketchy, but that was the general gist of his theory.

 

 >From a philosophical perspective, I have serious issues with the concept of the Big Bang.  How can something appear from nothing?  Everything else in the universe has some sort of continuance from one form into another (except perhaps consciousness, but let's leave that for another discussion).  Why is there an exception made for the Big Bang?  Where did all this matter and energy come from?  These are answers that scientist do not have an answer too.

 

Is the Big Bang theory "pseudoscience"?  I'm not sure I would classify it in that category yet.  Despite my philosophic misgivings toward the theory, there is a lot of evidence that points in that direction.  And as long as there are clear ways to falsify the theory, then it can be consider a legitimate theory of science.

 

However, as the Big Bang theory progresses, they have been introducing concepts that are completely foreign to an objective view of the world. Such things as "dark matter" and "dark energy", which are completely undetectable entities, are necessary to satisfy the equations of the Big Bang theorists.  This in and of itself, serious destroys the credibility of their theory.

 

I'm not aware of any "Objectivist" physicist per se, but I'd assume that if there were any, they'd probably see the same limitations in the Big Bang theory that I do.  Those are my two cents.

 

From: Eyal Mozes To: "" <objectivism Subject: Re: OWL: Big Bang Date: Fri, 18 Feb 2005 13:44:14 -0500

 

I am not aware of any published articles by Objectivist physicists on the subject of the Big Bang; I would be interested in any info about such publications.

 

I have heard many informal discussions of the Big Bang theory by Objectivists, and have seen two main objections raised to it. John Drake raises both of these objections in his February 17 message.

 

One objection is that Big Bang theory seems to imply that existence has originated out of non-existence. I dealt with this objection in an answer on TOC's Q&A site in July 2003 (http://www.objectivistcenter.org/objectivism/q-and-a-answer.asp?QuestionID=78).

As I explain there, the mainstream versions of Big Bang theory don't really have that implication; this is a valid objection to the ideas of some fringe advocates of Big Bang theory, but not to the theory itself.

 

The second objection, however, does point out a serious problem inherent in Big Bang theory. The theory assumes the existence of "dark matter"; a kind of matter that is undetectable by any currently known technology, and about which nothing is known other than that it has mass. Not only does Big Bang theory assume that this mysterious "dark matter" exists; it assumes that it exists in a total mass approximately 10 times greater than all the matter that we observe through our senses or by technological means. There is no empirical evidence at all for "dark matter"; the only reason it is accepted by physicists is that Big Bang theory requires its existence.

 

Objectivists believe that scientific theories should be based on the observed evidence. And they accept the principle of Occam's Razor, that a theory should not multiply entities beyond necessity. The assumption of "dark matter" in Big Bang theory seems like a clear violation of these principle; it asserts the existence of entities on a truly massive scale, without support by any observed evidence, just to fit a theory. Assertions about the existence of "dark matter" can be an excellent fertile source for entertaining fictional speculations (see Philip Pullman's "His Dark Materials" trilogy as the best example); but when it is accepted as a serious scientific theory, there is good reason to object to it.

 

From: Christopher A Robinson To: objectivism Subject: OWL: Reverse Uniformitarianism and the Big Bang Date: Sat, 19 Feb 2005 08:34:00 -0600

 

I am not yet finished with Harriman's lectures, so I don't know whether he says whether he supports the big bang or not. In another ARI lecture, however, Lisa Van Damme calls the big bang idea "fairy tale science."

 

Having said that, I want to deal with some of John Drake's comments on the big bang that I think reveal why ARI is opposed to this and why I think the opposition is unjustified..

 

1. The most straightforward evidence for the big bang is an application of a principle that can be called reverse uniformitarianism: That is, we take the processes that we observe going on now and run them backward to determine some previous state. So, we observe the continents along the Atlantic ocean spreading apart now; if we reverse the procedure, then we come to a time when they would be together. At this point, we could look for evidence that they were together at that time. The same procedure can be used whenever there is any gradually changing process that has been continuing for a time period (e.g., languages, planetary positions, genetic evolution).

 

With the big bang model, the process we observe is the galaxies spreading apart. Naturally, if one worked the process backwards there would be a time when they are all together. There is other evidence that has been predicted (e.g., cosmic background radiation) that we also observe that has been taken as independent support of this idea.

 

2. The Big Bang gives rise to a great many difficulties, some physical and some philosophical, but to no real difficulties in Objectivist metaphysics. On the physical level, the pressure and temperature in the primordial substance are unlike anything on earth, and so understanding the nature of this has proven difficult. The philosophical difficulties seem more difficult. It is difficult for many to accept that matter as we know it had a beginning. However, this is not a real problem. The apparent problem exists because of a common equation of matter with existence. This is false: existence does not mean matter.

 

Peikoff, in his summary of Objectivism, makes the point clearly: the concept of existence "does not specify that the physical world exists" (1991, p. 5). Rand makes the same point in her treatise on epistemology,

 

For instance, we couldn't say: everything is material, if by "material" we mean that of which the physical objects on the perceptual level are made-"material" in the normal, perceptual meaning of the word. If this is what we mean by "material," then we do not have the knowledge to say that ultimately everything is sub-subatomic particles which in certain aggregates are matter (1990, p. 290; cf, also, pp. 245-251).

 

Objectivism holds that the universe is eternal. As Peikoff writes,

Now let me reiterate that the causal link relates an entity and its action. The law of causality does not state that every entity has a cause. Some of the things commonly referred to as "entities" do not come into being or pass away, but are eternal- e.g., the universe as a whole. The concept of "cause" is inapplicable to the universe; by definition, there is nothing outside the totality to act as a cause. The universe simply is; it is an irreducible primary. (1991, p. 16).

 

So, Objectivism makes a distinction between existence and matter. The universe, existence as a whole, is eternal, but there is not the necessary presumption that matter is. If matter is not inherently eternal, there is no problem with it coming into existence. In sum, the Big Bang model is not inherently a creation ex nihlo, but rather a view that matter as we know it had a cause. Since existence, in whatever form, has identity, the primordial stuff, whatever is was, would operate causally.

Christopher Robinson

 

From: Christopher A Robinson To: objectivism Subject: OWL: Newton's Laws Require Dark Matter

Date: Sun, 20 Feb 2005 01:08:24 -0600

 

Several people have wailed against one particular idea that they associate with big bang cosmology: dark matter. Whatever the merits of specific aspects of big bang cosmology, and the importance of dark matter in that cosmology, the proposed existence of dark matter is a separate issue from big bang cosmology. It is not an arbitrary postulate, and there is direct evidence for it. The majority of this evidence comes from the discrepancy between the velocities of objects and the mass necessary for those velocities.

 

The postulation of dark matter can be traced back to Jan Oort's studies of the motions of stars within our galaxy (North, 1995, p. 499). Using Newton's modifications of Kepler's third law of motion, Oort could relate the velocity of these stars with the masses of the object they were orbiting (basically, the mass of the inner part of the galaxy). When solving these equations, Oort found that the mass required for the stars' velocities was greater than the visual mass in our galaxy. Oort's, and those who followed him, natural inference was that there must be dark matter; that is, there must be matter that is too cool to release detectable radiation. In other words, Newton's laws require the existence of dark matter to explain the velocities of Oort's stars.

 

Further support for this idea comes from studies of the motions of clusters of stars around galaxies and from the motion of other galaxies (Silk, 1994). As before, the mass necessary to explain the velocities of the objects is greater than the observed mass. While there are no established values for this, it is clear that the amount of dark matter is immense--equal to and perhaps up to 95% greater than the amount of visible matter.

 

The amount of dark matter has assumed a great importance, as this value determines the ultimate destiny of the universe. If there is a critical amount, the expansion of the universe-as-we-know-it will eventually slow and the universe will collapse back onto itself--perhaps to explode again. If, however, there is less then the universe will expand forever and the end will be a big freeze.

 

There is a lot of speculation, some of it absurd, about the nature of this dark matter. It could be, and probably is, nothing more exotic than faint stars, super planets, dying white dwarf starts, and the like. With that in mind, the evidence for dark matter's existence is solidly based on applications of Newton's laws and is independent of the validity of general big bang cosmology.

Christopher Robinson

 

From: Brett Mukherjee Hoffstadt  To: <objectivism Subject: Re: OWL: Big Bang Date: Sat, 19 Feb 2005 13:55:58 -0500

 

On NPR today there happened to be an interview with an author who has written about the Big Bang.  I didn't catch the name on the radio, but it might have been a Mr. Singh who has a recently published book about it also.

 

Anyway, he pointed out that a good theory will be able to provide predictions for future evidence or tests, and the Big Bang theory has done this in many instances.  Two he pointed out were the ratio of Hydrogen to Helium in the Universe (the theory contends that the initial fusion nuclear reactions would combine H into He in a certain ratio, which is exactly what we observe), and the existence of background microwave radiation left over from the initial explosion, which exists in exactly the frequency range predicted by the theory.  Both of these facts were discovered after the theory's predictions were made.  These facts seem to provide some firm support for the theory.  And it seems that every year we hear about more discoveries that support or are consistent with, rather than contradict, the theory.

 

A third fact is that the Universe is known to be expanding in all directions, consistent with it originating in a smaller or single point.

 

Of course, this could be a coincidence, but if all these facts seem to fit a theory, until another more credible and helpful theory emerges, the Big Bang seems to be the most rational one to hold.

Regards,

  Brett

--

Brett Hoffstadt

Queens, NY, USA

"May you live all the days of your life." Jonathan Swift

 

From: Tyrrell McAllister To: <objectivism Subject: Re: OWL: Big Bang Date: Sat, 19 Feb 2005 21:15:38 +0100

 

John Drake (Feb 17) and Eyal Mozes (Feb 18) argue that the theory of the Big Bang is flawed because it assumes the existence of dark matter.  Mozes writes, >Objectivists believe that scientific theories should be based on the observed evidence. And they accept the principle of Occam's Razor,  that a theory should not multiply entities beyond necessity. The assumption of "dark matter" in Big Bang theory seems like a clear violation of these principle; it asserts the existence of entities on a truly massive  scale, without support by any observed evidence, just to fit a theory. Assertions about the existence of "dark matter" can be an excellent fertile source for entertaining fictional speculations (see Philip Pullman's "His Dark Materials" trilogy as the best example); but when it is accepted as a serious scientific theory, there is good reason to object to it.

 

I was hoping someone could elaborate on how the Big Bang theory assumes the existence of dark matter?  My understanding is that dark matter is believed to exist because we directly observe collections of mass, such as galactic clusters, where there is insufficient visible matter to provide the necessary gravitational force to hold them together.

 

The only option besides dark matter is that some non-gravitational force is holding those clusters together.  Perhaps the theories of Eric Lerner that Drake referred to are along these lines.  I'm not familiar with Lerner's work.  However, so far as I know, no force besides gravity has ever been observed to operate over inter-galactic distances, so such theories have their own violations of parsimony to justify.

 

Besides, it is not valid to use Occam's Razor to reject theories that imply the existence of entities that we haven't directly observed. The appropriate use of Occam's Razor is as a means of selecting among several rival theories.  If theory A and theory B both explain the same observations, but theory A requires the existence of fewer unobserved phenomena, Occam's Razor tells us that we should prefer theory A.

 

Note also that Occam's Razor states that entities should not be multiplied *beyond necessity*.  It does not tell us that unobserved phenomena should not be introduced at all.  In fact, the criterion of falsifiability tells us that every scientific theory should predict a phenomenon that has not yet been observed, at least at the time that the theory is introduced.  After all, if a theory only tells you stuff that you've already observed, how can it be falsified?

 

But if you want to show that the hypothesis of dark matter is introducing entities *unnecessarily*, then you need to provide an alternative explanation for the observed phenomena that requires fewer assumptions.  Maybe Lerner has done this, maybe not.  But I doubt that he has done so without introducing unobserved phenomena of his own.

 

From: Eyal Mozes To: "" <objectivism Subject: Re: OWL: Big Bang Date: Mon, 21 Feb 2005 10:08:55 -0500

 

Let me first make clear that I am not a physicist or astronomer, and am talking from an informed layman's understanding. If there are professional physicists or astronomers on OWL who could weigh in with more detailed explanations, I would be very interested.

 

Tyrrell McAllister writes:

 >I was hoping someone could elaborate on how the Big Bang theory assumes the existence of dark matter?  My understanding is that dark matter is believed to exist because we directly observe collections of mass, such as galactic clusters, where there is insufficient visible matter to provide the necessary gravitational force to hold them together.

 

Not exactly; the question is not what's holding galactic clusters and individual galaxies together at the present. The question is how they were originally formed; if there were a Big Bang, visible matter would not have provided nearly enough gravitational force to then draw matter into such clusters. The answer of Big Bang theory is that the gravitational force is provided by "dark matter", which exists in a total mass 50 to 100 times larger than that of visible matter (in my last message I was writing from memory, and mistakenly said it is 10 times).

 

The main rival to Big Bang theory, as far as I know, is Hannes Alfven's "plasma cosmology", presented in popular form by Eric Lerner in "The Big Bang Never Happened". It explains the formation of galaxies and galactic clusters by the operation of electrical attraction forces between clouds of plasma (over a period of time much longer than the time supposed to have passed since the Big Bang). This is an unobserved phenomenon, but it is a logical extension of observed entities and forces, and by a reasonable application of Occam's Razor it is clearly better than a massive introduction of new and completely unknown and unobserved entities like "dark matter".

 

As for the "Hubble shift" (the observed motion of galaxies away from each other), Lerner goes over several competing theories that have been proposed to explain it. Each of these theories has problems, and as far as I know there is no epistemological justification for accepting any one of them; but Big Bang theory, with its introduction of "dark matter", seems the least plausible.

 

Christopher Robinson writes that there is other evidence for dark matter, other than that it is assumed by Big Bang theory. I find Christopher's discussion confusing, and it contradicts what I've read on the subject. (Christopher, it also looks to me like your post was cut and pasted out of some longer piece, and without paying sufficient attention to making your post self-contained. You make references to "North, 1995" and "Silk, 1994", without actually giving the references.) I'd be interested to hear more from Christopher, and I may be wrong on this, but my impression is that he is confusing between dark matter and black holes.

 

Black holes are not directly visible with a telescope, but they are a natural consequence of Newton's laws; they are composed of the same visible matter familiar to us, only at much greater densities; and they have been observed indirectly, through their gravitational effect on the motion of nearby stars. There's nothing particularly mysterious about black holes; and, as Christopher says, the accepted theory is that they are formed from dying white dwarf stars. However, I'm not aware of anyone who's suggested that black holes comprise more than a small fraction of the total mass of our galaxy, or of all matter in the universe; they are totally separate from "dark matter", assumed by Big Bang theory to exist in a total mass much larger than that of observed matter.

 

From: "Marnee Dearman" To: <objectivism Subject: OWL: Alternative to Dark Matter: Plasma

Date: Mon, 21 Feb 2005 11:36:15 -0700

 

"My understanding is that dark matter is believed to exist because we directly observe collections of mass, such as galactic clusters, where there is insufficient visible matter to provide the necessary gravitational force to hold them together." -- Tyrrell McAllister

 

Eric Lerner, on his website,  http://www.bigbangneverhappened.org/ elaborates on this.  He claims that there is observational evidence of the existence of 'warm' and 'hot' plasma that is dense enough (and abundant enough) to account for the gravitational effects attributed to dark matter:

 

"There is extensive observational evidence for ordinary matter in two other forms that are relatively dim, one is white dwarfs in the halos of spiral galaxies. Recent observations of high proper motion stars have shown that halo white dwarfs constitute a mass of about 1011 solar masses, comparable to about half the total estimated mass of the Galaxy [R.A. Mendez and D. Minnitti ,Astrophys. J., vol. 529, p.911; B.R. Oppenheimer et al Science, 292, p. 698]. While these observations have been sharply criticized, they have been confirmed by new observations [R. A. Mendez ,arXiv:astrop-ph/0207569]."

 

"Observations of ultraviolet and soft x-ray absorption has revealed the existence of "warm plasma' with a temperature of only about 0.2keV, which amounts to a mass comparable to that of the entire Local group of galaxies.(Nature 421, 719). If we add up the warm plasma, which is sufficiently dim to be observable only as it absorbs radiation from more dint objects, the hot plasma, and the white dwarfs, we have enough matter to equal that which is inferred by the gravitational mass of cluster of galaxies. So there is no need for non-baryonic matter and there is no room for it either."

 

See the section titled "Dr. Wright is Wrong" for this discussion.

 

I also suggest reading the sections "Open Letter" http://cosmologystatement.org/ and "Recent Discoveries" [Recent discoveries pose more problems for Big Bang].

 

$

Marnee

 

From: Ellen Stuttle To: objectivism Subject: OWL: Scientific American: Big Bang Article

Date: Mon, 21 Feb 2005 13:41:03 -0500

For those interested in the subject of the big bang:

 

The March 2005 issue of Scientific American has an article titled "Misconceptions about the Big Bang."

 

(On the front cover the article is advertised with the description:

 

Big Bang Bungled:  6 Common Errors about the Expanding Universe.)

 

I haven't yet had time to read the entire article myself, but I've read all the inserts and studied the diagrams and read about half of the article.  Thus far it looks like a quite accurate presentation of what the theory is and of the evidence supporting the theory.

Ellen Stuttle

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