Dark Energy

By Michael on October 5, 2007 at 8:55 pm | In Astrophysics, Blog Posts | 4 Comments

“Dark energy” is the phrase we use to describe an observed phenomena. That phenomena is the acceleration of the expansion of the universe. Wikipedia explains:

In 1998 observations of Type Ia supernovae suggested that the expansion of the universe is speeding up. In the past few years, these observations have been corroborated by several independent sources: the cosmic microwave background, gravitational lensing, age of the universe and large scale structure, as well as improved measurements of the supernovae.

When Einstein developed general relativity, as is well known, he added a factor to his equation because it was necessary to reproduce the universe he thought we lived in — a static universe with no expansion or contraction. When we observed that the universe was not only expanding but accelerating in its expansion, that extra term in the equation was already there to express it.

That term is capital lambda (Λ). It’s a pressure term, in one way of thinking. Just like a gas or a fluid has pressure, it appears the universe has some sort of pressure. In another way of thinking, Λ is an energy because pressure and energy density are related in a linear way. So there is an apparently uncompensated energy that results in a universe that is out of balance — it’s being very slowly blown apart.

So, like dark matter, dark energy is “real”, in this case “real” meaning that it’s a name for something that we really do observe. Some people are uncomfortable with this. They think, in the example of dark energy, that we don’t need an extra term in the equation, the rest of the equation is somehow wrong. That is, of course, another perfectly valid option. Either physics is wrong or dark matter/energy exist or both!

But don’t be fooled — the phenomena are real. We really do find an unaccounted for gravitational influence (dark matter) and we really do see something acting like a pressure in our cosmology (dark energy). This is not philosophy, it’s science and it’s very good science at that. The fact that there are still things we don’t know is the fun part!


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  1. But don’t be fooled — the phenomena are real. We really do so find an unaccounted for gravitational influence (dark matter) and we really do see something acting like a pressure in our cosmology (dark energy). This is not philosophy, it’s science and it’s very good science at that. The fact that there are still things we don’t know is the fun part!”

    How can you be so sure that dark energy and dark matter exists? Very prominent physicists like James Clerk Maxwell thought that the aether really existed and encouraged others to actively look for it.

    It, like dark energy and dark matter, kept the old tried and true theory in place.

    But you know serious anomalies crop up in physics like the photoelectric effect and the ultraviolet catastrophe and a serious which require a paradigm shift that revolutionizes our beliefs about physics.

    There is a coincidence between the dimmingdimming of the universe and its acceleration. They both occurred around z = 1. They could not be causally connected could they. What does light have to do with gravity you may ask? I can get an 84 % increase in gravitational mass of a nichrome wire and mica assembly that spews out infrared radiation. And I have performed other experiments confirming that spreading infrared radiation is gravitationally attractive.

    Comment by pbfred — October 11, 2007 #

  2. How can you be so sure that dark energy and dark matter exists?

    Well, my main point is that the physical basis for them existing is real. The explanations may be wrong, but explanations are needed.

    You guys always bring up the aether when you want to introduce some crazy theory. I’m all for crazy theories but you should publish them in peer-reviewed journals and be famous if you are correct. The science speaks for itself yet so many people with wildly alternative theories never publish them in serious journals. Einstein, you’ll recall, published his results. Dark energy is something Einstein himself came up with, in a way. He had some crazy theories and yet he published them and became international famous.

    If you really think you are correct, you should publish your results in a world-class, peer-reviewed journal of physics.

    Comment by michael — October 11, 2007 #

  3. I have to get somebody like you to read my paper, question my experimental procedure and come to the conclusion that my explanation of the dark energy problem makes sense. I could submit a paper but if the referee has an a belief system like you have I do not have a chance getting it accepted.

    You call me crazy. But what does my state of mind have to do with my experimental results. Am I dishonest and have I faked the results? Is that how you dismiss them?

    In addition to a decrease in weight I can also get an increase. So you cannot claim my results are due to some sort of hot air buoyancy effect. Here I get a 23% or a 0.41 N increase in weight with a hot plate heating element. The hot plate heating element initially has a downward force of around 1.7 N. This is a substantial amount of weight. It increases to about 2.1 N after heat has been applied.

    Gravitational mass is supposed to be the same as inertial mass. My results apparently violate the principle of equivalence on which Einstein’s General Relativity depends. There is theoretical paper saying that only at zero degrees Kelvin are gravitational mass and inertial mass equivalent. Maybe this paper will get you to focus on my theory and experiments.

    Comment by pbfred — October 12, 2007 #

  4. I’m using the term “crazy” to mean ideas vastly different from our standard models. You’ll see above that I refer to Einstein as having crazy theories, too. So that is not an insult, just a manner of speaking.

    I don’t believe that scientists have belief systems. If your experiment is correct and revolutionary, I believe it would get published. My point above was that people like you, meaning people with revolutionary theories outside of the standard model, make very little effort to get into the mainstream. Why is that? I get all sort of email from people with “crazy” ideas and they all come across as this anti-establishment crowd unwilling to present their results in peer-reviewed journals. They so want our current models to be wrong.

    Have you actually studied General Relativity? Have you looked at the thousands of papers and experiments that support it? It is rigorous as hell and has been hammered on by skeptics for 100 years. Your experiments look interesting but the interpretation is nothing short of bizarre, IMHO.

    For example, it’s been proven repeatedly that gravitational force is proportional to the mass. The luminosity is not proportional to mass. Stars 10 times more massive than the sun are 10,000 times more luminous. Your rational on the vibration of molecules creating a force inward seems naive to me. More molecules “above” force the momentum inward? That’s daft considering the cross-section of a molecule as a fraction of the radius of the star at that point. It’s a plane for all practical purposed on that scale. Heat is isotropic, it’s practically the definition of heat. We know and use the fact that radiation produces on outward pressure. That and gas pressure oppose gravity to make a star stable. So radiation produces both the gravity and the force that counteracts it?

    I’m not trying to be harsh. The bar is quite high if you want to produce entirely new physics. Einstein did it. He was like you and he convinced all the skeptics because of the rigor of his work and the testable (and tested!) predictions that came directly out of his theories.

    If your results about infrared light changing the weight of objects is true, publish it in a real journal! From your web page alone I can’t tell how rigorous your method is or if your results are valid. If they are, I congratulate you on some very interesting work! But you can’t sit back safely on your web site, you have to publish them in a peer-reviewed journal.

    Comment by michael — October 12, 2007 #

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