What We Know about Cosmology

And what we might hope to discover, according to the new book Brave New Universe.

The universe. [CREDIT: colour-universe.de]
By | Posted January 17, 2007
Posted in: Featured, Physical Science
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Brave New Universe: Illuminating the Darkest Secrets of the Cosmos

By Paul Halpern and Paul Wesson. Joseph Henry Press, 2006. $27.95

Since the extent of my knowledge of the cosmos comes from a college Astronomy course, I’ve been longing to know what scientists actually understand about the cosmos today. When I read on the flap of Brave New Universe that the book offers a “guided tour of current advances and controversies in cosmology,” I thought this would be a perfect place to begin my quest. I wasn’t disappointed—though laypeople like myself may have to read carefully at times to wrap their minds around some key concepts.

The book covers human knowledge of the cosmos from the early contributions of Kepler and Newton to Einstein’s theory of general relativity. The authors describe how technology has opened the doors to more advanced theories like quantum physics and string theory. Yet as we developed the tools to observe farther out into space or deeper into the makeup of atoms, our questions become more complicated—and thus harder to answer. The book’s later chapters delve into the strange realms of theoretical astrophysics, explaining the theories currently being pondered by the world’s most brilliant cosmologists to readers who can keep up.

The book begins with the questions that surrounded the theory of relativity when Einstein developed it in 1905. It goes on to cite the evidence that has led us to the solid conclusions we have today about our universe—such as how observations of starlight being bent by the sun’s gravity offered proof of general relativity, and how background radiation discovered by Bell Labs scientists Arno Penzias and Robert Wilson in 1965 is the most definitive evidence we have for the Big Bang.

The reader also learns that contributions from scientists Edwin Hubble and Alexander Friedmann have allowed us to discern that all the galaxies are fleeing from each other in an expanding universe whose geometry is flat, meaning it will expand forever. Through their work, we’ve also learned that the universe’s expansion is accelerating.

After readers learn how cosmologists have made substantial conclusions about the age of the universe (currently estimated at 13.7 billion years old) and its geometry, the authors tackle the latest challenges for the field: hitherto unanswered questions regarding dark matter, dark energy and the possibility of natural constants that fluctuate over time. Through the latter half of the book, the authors dive deeply into the world of theoretical astrophysics as it exists today, touching on concepts hard for a mere mortal to grasp.

For example, what if the constant of gravity is becoming weaker? What about the speed of light—has it always been the same? Scientists are investigating these questions in an attempt to account for the existence of dark matter and dark energy, the mysterious forces that make up a significant portion of the missing matter in the universe.

By the final chapters, the reader is swimming in string theory and its successor, M-theory, and is trying to digest the complicated notion about the existence of a fifth dimension expressed in terms of mass—an idea as hard to understand as a fourth dimension of time. As Astronomy-101 classes don’t cover concepts more complicated than the dimensions of space-time, many readers will have little basis for understanding such strange but fascinating ideas.

Yet the authors have done a decent job of remembering their non-cosmologist audience throughout the rest of the book. Halpern and Wesson bring characters like Kepler, Newton and Einstein to life, showing that they, too, were actively testing and revising their theories just like today’s string theorists. The book does a tremendous job of showing that cosmology is not a hard set of facts verified by their place in astronomy textbooks. Rather, it is an amorphous subject in need of constant rethinking and reworking based on our continuously expanding understanding of the universe (think of Pluto’s recent demotion from planet to dwarf planet).

We are also limited by our understanding, the authors say, since there is so much of the universe we still don’t know. “Photon by photon, we slowly drink in one particular type of cosmic energy, leaving us ample time to savor (and interpret) this brew,” Halpern and Wesson write. “As connoisseurs of such stellar ferment, we pride ourselves in our growing appreciation of what we sip. Yet we also realize that much lies in the bottom of the barrel, inaccessible to our tasting, and all this could have quite an alien flavor.”

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  1. TESTS FATAL FOR SPECIAL RELATIVITY

    Recently a relativist explained the triumph of special relativity over all tests

    Tom Roberts: “Experimental Tests of Special Relativity”

    but failed to refer to the principle of VARIABILITY of the speed of light brilliantly discussed by him on the forum sci.physics.relativity:

    Pentcho Valev asked on sci.physics.relativity: CAN THE SPEED OF LIGHT EXCEED 300000 km/s IN A GRAVITATIONAL FIELD? Tom Roberts answered: “Sure, depending on the physical conditions of the measurement. It can also be less than “300000 km/s” (by which I assume you really mean the standard value for c). And this can happen even for an accelerated observer in a region without any significant gravitation (e.g. in Minkowski spacetime).” Tom Roberts tjroberts@lucent.com

    The variability of the speed of light in a gravitational field and, equivalently, for an accelerated observer, was introduced by Albert Einstein and then tested and confirmed by his disciples, although in a somewhat subdued manner:

    http://www.physlink.com/Education/AskExperts/ae13.cfm : “So, it is absolutely true that the speed of light is _not_ constant in a gravitational field [which, by the equivalence principle, applies as well to accelerating (non-inertial) frames of reference]….Indeed, this is exactly how Einstein did the calculation in: “On the Influence of Gravitation on the Propagation of Light,” Annalen der Physik, 35, 1911. which predated the full formal development of general relativity by about four years. This paper is widely available in English. You can find a copy beginning on page 99 of the Dover book “The Principle of Relativity.” You will find in section 3 of that paper, Einstein’s derivation of the (variable) speed of light in a gravitational potential, eqn (3). The result is, c’=c0(1+V/c^2) where V is the gravitational potential relative to the point where the speed of light c0 is measured.”

    The question is: The variable speed of light that the accelerated observer measures obeys an equation equivalent to c’=c(1+V/c^2) and this equivalent equation is……??? Relativists know the equivalent equation is c’=c+v where v is the relative speed of the light source and the observer. They also know Einstein’s prophecy: “If the speed of light is the least bit affected by the speed of the light source, then my whole theory of relativity and theory of gravity is false.”

    Relativists used to rely on the fact that the observer is refered to as ACCELERATED; this gave them the opportunity to raise arguments of the sort: Since the observer is accelerated, this has nothing to do with special relativity. Now relativists know those arguments were totally irrelevant. It is time to remember another prophecy of Einstein’s: “I consider it quite possible that physics cannot be based on the field concept,i.e., on continuous structures. In that case, nothing remains of my entire castle in the air, gravitation theory included, [and of] the rest of modern physics.”

    Pentcho Valev
    pvalev@yahoo.com

    Pentcho Valev, January 17, 2007 at 3:59 am
  2. interesting article

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    Darius, January 18, 2007 at 5:06 am
  3. EINSTEIN’S SECOND LAW

    http://www.physicstoday.org/vol-60/iss-1/12_2.html :
    “Why no Einstein’s laws? Since my undergraduate days, I have been puzzled by the fact that we have Newton’s laws of motion but only Einstein’s theory of special relativity. We have finished celebrating the 100th anniversary of the publication of the theory of special relativity, and it seems to me that after a century of validation, it’s time to rename it as more than just a theory. I propose that we, as physicists, define a set of Einstein’s laws, just as we have Newton’s laws, Coulomb’s law, or Faraday’s law. I begin the discussion by offering the following three laws: The laws of physics are identical in all non-accelerating (that is, inertial) frames. The vacuum speed of light, c, is the same for all inertial frames. The total energy E of a body of mass m and momentum p is given by E = [√m2c4 + p2c2]. In particular, the energy of a body measured in its own rest frame is given by E = mc2, and the energy of a massless body is E = pc.”

    Consider again Einstein’s Second Law:

    Einstein’s Second Law (original version): “The vacuum speed of light, c, is the same for all inertial frames.” (In fact, the original 1905 version of Einstein’s Second Law was a bit different but this is irrelevant here.)

    This extremely important Law was improved by Einstein himself in the following way:

    Einstein’s Second Law (improved): The observer’s frame may be inertial but if the observer and the light source are at different gravitational potentials, the speed of light is variable and obeys the equation c’=c(1+V/c^2), where V is the gravitational potential relative to the light source.

    This improved version of Einstein’s Second Law was gloriously confirmed in 1960 when Pound and Rebka measured a gravitational redshift factor equal to 1+V/c^2. Then clever Einsteinians deduced the ultimate version of Einstein’s Second Law:

    Einstein’s Second Law (ultimate version): If the relative speed of the observer and the emitting body is zero, light is always propagated in empty space with a variable speed c’=c(1+V/c^2) where c is the initial speed of photons relative to the emitting body and V is the gravitational potential relative to the place of emission. Equivalently, if the observer and the place of emission are at the same gravitational potential, light is always propagated in empty space with a variable speed c’=c+v where v is the relative speed of the observer and the emitting body.

    Clever Einsteinians were going to inform the world about the ultimate version of Einstein’s Second Law but suddenly they realised the ultimate version was incompatible with the original version. The money-spinner called the theory of relativity was in danger so clever Einsteinians postponed the publication of the ultimate version until some new money-spinner was devised.

    Pentcho Valev
    pvalev@yahoo.com

    Pentcho Valev, February 11, 2007 at 5:03 am
  4. HYPOCRISY OR WHY THEORETICAL SCIENCE DIED

    LINK
    “A Crisis in Fundamental Physics…Then, about 30 years ago, something changed. The last time there was a definitive advance in our knowledge of fundamental physics was the construction ofthe theory we call the standard model of particle physics in 1973. The last time a fundamental theory was proposed that has since gotten any support from experiment was a theory about the very early universe called inflation, which was proposed in 1981.”

    http://www.logosjournal.com/issue_4.3/smolin.htm
    “Quantum theory was not the only theory that bothered Einstein. Few people have appreciated how dissatisfied he was with his own theories of relativity. Special relativity grew out of Einstein’s insight that the laws of electromagnetism cannot depend on relative motion and that the speed of light therefore must be always the same, no matter how the source or the observer moves. Among the consequences of that theory are that energy and mass are equivalent (the now-legendary relationship E = mc2) and that time and distance are relative, not absolute. Special relativity was the result of 10 years of intellectual struggle, yet Einstein had convinced himself it was wrong within two years of publishing it.”

    Has the author of the two texts (Lee Smolin) ever seen the close relation between them? Surely he has.

    Pentcho Valev
    pvalev@yahoo.com

    Pentcho Valev, February 21, 2007 at 2:47 am
  5. NEWTON VERSUS EINSTEIN IN THE ROYAL SOCIETY

    Some time ago the Royal Society conducted a poll that gave a conclusion more or less like “Newton is greater than Einstein”:

    http://www.royalsoc.ac.uk/news.asp?id=3880

    This conclusion is misleading. In terms of initial principles the only difference between Newton and Einstein is that Newton regarded light as DISCONTINUOUS particles whose speed, like the speed of other particles, could only be VARIABLE (varies with the speed of the light source), whereas Einstein based his theory on the concept of light as a CONTINUOUS field and postulated that the speed of light was CONSTANT (independent of the speed of the light source). The importance of this initial difference was given by Einstein himself:

    Einstein: “If the speed of light is the least bit affected by the speed of the light source, then my whole theory of relativity and theory of gravity is false.”

    Einstein again: “I consider it quite possible that physics cannot be based on the field concept, i.e., on continuous structures. In that case, nothing remains of my entire castle in the air, gravitation theory included, [and of] the rest of modern physics.”

    So Newton cannot be just greater than Einstein. Either the speed of light is independent of the speed of the light source and then Einstein has improved Newton’s theory, or the speed of light does depend on the speed of the light source and then Einstein has destroyed modern physics. A new poll is necessary where the question should be: “Who was right about the speed of light?”. In a normal world such problems would not be resolved in polls but in Einstein’s world that is the only choice.

    Pentcho Valev
    pvalev@yahoo.com

    Pentcho Valev, March 1, 2007 at 2:25 am
  6. HOW FRAGILE SCIENCE IS

    At first sight, Einstein’s crime is a small crime. Initially he adopted the emission theory of light, c’=c+v, where c’ is the speed of photons as measured by an observer, c=300000km/s is the CONSTANT speed of the photons RELATIVE TO THE LIGHT SOURCE and v is the relative speed of the source and the observer. Then he realized it would be more profitable for him to become a divine creator of miracles (time dilation, length contraction etc.) and accordingly introduced the false principle of (absolute) constancy of the speed of light, c’=c:

    John Norton, “Einstein’s Investigations of Galilean Covariant Electrodynamics prior to 1905”

    In the end Einstein realized the false principle of (absolute) constancy of the speed of light was too dangerous and partially restored the truth by recognizing that the speed of light varied with the gravitational potential (see Chapter 22 in his “Relativity”). However his miracles killed theoretical physics (it was already half dead since entropy miracles had been ravaging for 50 years). So nowadays Einsteinians make money essentially in two ways. On one hand, they continue to destroy human rationality by teaching Einstein’s miracles; on the other, they constantly “improve” Einstein’s theory by camouflaging the antecedent of the miracles, the false principle of (absolute) constancy of the speed of light. Einsteinians can even go so far as to say Einstein’s special relativity is wrong:

    http://www.logosjournal.com/issue_4.3/smolin.htm “Quantum theory was not the only theory that bothered Einstein. Few people have appreciated how dissatisfied he was with his own theories of relativity. Special relativity grew out of Einstein’s insight that the laws of electromagnetism cannot depend on relative motion and that the speed of light therefore must be always the same, no matter how the source or the observer moves. Among the consequences of that theory are that energy and mass are equivalent (the now-legendary relationship E = mc2) and that time and distance are relative, not absolute. Special relativity was the result of 10 years of intellectual struggle, yet Einstein had convinced himself it was wrong within two years of publishing it.”

    Scientists would not react to Einsteinians’ discovery that special relativity is wrong. They know: just another original way of making money.

    Pentcho Valev
    pvalev@yahoo.com

    Pentcho Valev, March 5, 2007 at 2:44 am
  7. HOW EINSTEINIANS UNDERSTAND SCIENCE

    http://www.phil-inst.hu/PIRT.Budapest : “Mathematics, Physics and Philosophy in the Interpretations of Relativity Theory” – Budapest, Hungary, 7-9 September 2007. Objectives: “While the organizing committee encourages critical investigations and welcomes both Einsteinian and non-Einsteinian (Lorentzian, etc.) approaches, including the recently proposed ether-type theories, it is assumed that the received formal structure of the theory is valid and anti-relativistic papers will not be accepted.”

    Pentcho Valev
    pvalev@yahoo.com

    Pentcho Valev, March 24, 2007 at 2:51 am
  8. EINSTEINIANS WILL REFUTE EINSTEIN IN 2015

    http://www.msnbc.msn.com/id/17260859 : “LISA is scheduled to launch in 2015. “No one has detected gravitational waves yet. If LISA flies and works properly, it will detect gravitational waves from astronomical sources,” Richstone said. “If it doesn’t, then Einstein’s theory of general relativity is wrong.”

    In fact, Einsteinians tried to refute Einstein in 1960 but failed. At that time Pound and Rebka had measured a frequency shift

    f’=f(1+V/c^2)

    and many Einsteinians suspected that this result confirmed Einstein’s 1911 equation according to which the speed of light is variable:

    c’=c(1+V/c^2)

    However simultaneously Einsteinians discovered that nothing can refute Einstein’s theory, even Einstein’s own equations. Refutation is only possible in the distant future but, surprisingly, as the distant future approaches, it stops being a distant future and refutation becomes impossible again.

    Pentcho Valev
    pvalev@yahoo.com

    Pentcho Valev, March 29, 2007 at 8:02 am
  9. Pentcho Valev:

    I don´t know if this forum is still open, or whether you maybe have moved on to an alternative universe, where you are debating the relative merits of light propulsion and gravity propulsion for the string-vehicles used there.

    A difficulty I have with the consequences of Einstein´s Relativity Theory is that I can´t get an answer to several points that seem to me to be quite important. As I understand it, if you are overtaken by a photon, you will always measure its speed the same irrespective of your own speed.
    Unlike with a passing wahing machine, say, where you will measure its speed relative to you at the difference between your speeds. Then I don´t understand why clocks would keep different times according to their motion. I emailed a couple of professionals in the field, saying that I understand these things to have been shown experimentally to be so, but do they understand how they can be. They seem like a complete violation of the conclusions that quite simple logic would suggest. Magic? Books always say “counterintuitive”, with no further explanation. I also asked them if they understood, really understood, how the behaviour of particles could be affected just by our looking at them and also how the whole universe could be concentrated at a point at infinite gravity at the moment of Big Bang. What is infinite gravity? One physicist replied that no-one really understands these things and we just have to accept that they are so. The other sent me a whole lot of links to articles by him that did not answer these questions and recommended I read The Elegant Universe by Brian Greene. He also said that my belief that there must have been a reason for the universe to suddenly start from the most utmost nothing was a preconception and I was asking too much from the universe.

    robert, December 13, 2007 at 4:18 pm
  10. Speed of light is not the maximum speed at any object can travel in space. Normally gravitational waves and light can travel at the same speed but the speed of gravitational wave is much much higher as compared the speed of light in black holes. It is only on this account that light can not escape a black hole. Escape velocity at black hole is much higher than the velocity of light.

    Anirudh Kumar Satsangi, December 19, 2009 at 8:16 am
  11. In black holes gravitational force attracts electromagnetic force inside the black holes. It is evident that the magnitude of gravitational force in black holes is much higher as compared to that of electromagnetic force.

    Anirudh Kumar Satsangi, December 19, 2009 at 8:21 am
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