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Your title asks about dark matter, while the question asks about dark energy. The two are very different! I'd guess you mean to ask about dark energy because this does behave differently from matter (as far as gravity is concerned dark matter behaves just like ordinary matter). If so, the answer is that dark energy does not behave like exotic matter and ...


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Absolutely not. Dark matter has the same gravitational effects as regular matter it just doesn't interact electromagnetically. We expected a certain amount of dark matter, such a neutrinos, bit there weren't enough neutrinos so it seemed like there must be something else besides things like neutrinos. Something that interacts in the normal way ...


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There are many different forces which can affect various types of particles: electromagnetism, gravitation, weak force and strong force. These forces act in different ways to change the state of other particles which are sensitive to that particular force and transfer information from one part of the system to another via these interactions. ...


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Gravitational waves are not dark energy. Dark energy is closer to a fluid that is created when space expands and is destroyed when space is destroyed. That a fluid can do that requires a particular balance between energy and pressure one that is not normally achievable but if there were a fluid like that it would just keep filling everything. Classical ...


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The critical density is an observable quantity. $$\rho_C = \frac{3H_0^2}{8\pi G},$$ where $H_0$ is the present-day value of the Hubble parameter. $H_0$ is known (observationally) from a variety of methods to be 69 km/s per Mpc, with an accuracy of about 1 per cent. So to answer your question as posed, the critical density has a confidence interval of about ...


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This is all pretty well described in the Wikipedia page on the "big rip". The Friedmann acceleration equation determines the evolution of the scale factor of the universe and can be written as $$\frac{\ddot{a}}{a} = -\frac{4\pi G}{3}\left(\rho + \frac{3P}{c^2}\right) $$ where $\rho$ is the energy density, and $P$ is the pressure, usually parameterized as ...


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My understanding is that Hubble said the farther our we look into the Universe, the higher the redshift, therefore the faster things are moving. Pretty much. If you were some raisin in a rising cake, you'd say the same of the other raisins. But my question is, why is this surprising? It isn't. What was surprising is that the expansion rate is ...


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The first thing is to change your cartoon picture of Big Bang (an exploding egg of matter and energy). Big bang was not an explosion it was the start to expansion and the big bang theory tells the aftermath of this i.e. How the Universe evolved with time.What Hubble did observe was that the farther the galaxy or the source of light was faster it seemed to ...


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At the moment there does not exist a quantized unified theory of gravitation and the standard model. The only candidate to date is string theories which are at a research level, and in which I am not able to form an answer. There exist effective quantizations of gravity and effective models including the standard model in the studies of cosmology and the ...


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No-one knows what dark matter and dark energy are, so any comments on your question are necessarily speculative. Having said this, dark matter is generally considered to be just matter and the adjective dark is not meant to signify anything mysterious but merely that it doesn't interact with electromagnetic radiation or charge. The most popular suggestion ...


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The claim you cite from the radio does not claim anything relevant: A small motor powered by a 9v battery ran for about 2 hours with enough torque that they couldn’t stop it with their own hands. There is a large choice of gear motors available, you could choose a small one (as they report) that runs on 12V usually. It will use less energy when run ...



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