# Tag Info

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I personally find the terms consistent. Think of the entropy as Boltzman proposes: $S=k \, \ln W$ Meaning high entropy states can be realized via many different configurations. Truly ordered state (assume you arrange a sculpture from atoms) can be realized via much smaller number of microscopic states. So again, equilibrium is not order - it is a mess.

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What you are missing is the microscopic definition of entropy, once you know that, you will understand why people say that entropy is disorder. Equilibrium as order First, let's address your valid intuition that equilibrium as a form of order. Indeed, if everything is in thermal equilibrium, you just need to measure the temperature somewhere, and then you ...

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First of all as stated by Madan Ivan: equilibrium is not order. But you can get certain systems that are in a meta-stable "local" equilibrium (here meaning that you need some energy to move it from there), for example a crystal. These can be highly ordered. Intuitively: if you smack the crystal with a hammer it breaks to pieces. This brings your closer to ...

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There are lots of ways to make antimatter "naturally". One of the most common is pair production. A high energy photon is converted into a particle / anti-particle pair. For example, a photon with energy greater than about 1 MeV ($E > 2 \, m_\mathrm{electron}c^2$) can turn into an electron positron pair (some more considerations are needed to conserve ...

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Entropy is not disorder; it is a lack of information. Consider the entropy formula $S = k_b \log \Omega$. Here, $\Omega$ is the number of microstates (sets of particle positions/momenta) corresponding to an observed macrostate (something macroscopic we can observe, like 'the gas has volume $V$ and pressure $P$). What this formula means is that the entropy ...

3

Your question actually contains many questions, which are all related but not so strictly so that it is possible to give a full answer to it. Is every event in the universe related to each other? There are various ways to answer this question. Straight forwardly, we have observed that there is a finite speed at which information can propagate in our ...

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The dark energy density in the universe is about $7 \times 10^{-30}$g/cm$^3$ according to Wikipedia. This is uniform through out the Hubble volume of the entire universe i.e. the volume of the universe with which we are in causal contact. The Hubble volume is $10^{31} \ ly^3$ i.e. cubic light years. This gives $8.46732 \times 10^{84}$ cm$^3$ as the volume of ...

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No. Tides are caused by the gradient in the gravitational field. As you get further from the moon, the field drops as $\frac{1}{r^2}$ and the gradient changes as $-\frac{1}{r^3}$. If there is a gradient, then objects closer to the moon will accelerate towards it more rapidly than objects further away from it. The effect of this is nicely illustrated in an ...

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the cutting by universes is a way : to introduce possible new physics for each of these universes without leaving the homogeneity and isotropy cosmological principles, the known constants and the known physics of "our" universe to defer the infinity issue from our universe to a parent structure : the multiverse Homogeneity and isotropy are the main ...

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The answer to the title question (Is every event in the universe related to each other?) is clearly a no. Some events can't be related to others due to the fact that light has a finite and unsurpassable speed.

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In 1997 the Hubble discovered a large numbers of intergalactic stars. Others have since been discovered. It is now believed that about 1/2 of the stars in the universe may well be rogue stars that are located in intergalactic space. The AVERAGE density of intergalactic space is still very small, however, because of its immense size.

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Antimatter, although only in the form of positrons, is produced by many nuclides during the β⁺ decay. I can not get any reliable source, but vast majority of such β⁺ nuclides seem to be artificially prepared in a reactor, so this is perhaps not a truly natural source. Other article, named "Antimatter from bananas" states otherwise. The concentration of ...

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If you are talking of the visible Universe : We got from Planck mission : Ordinary matter 4.9% Dark matter 26.8% = 5.47 x Ordinary matter mass Dark energy 68.3% = 13.93 x Ordinary matter mass Wiki Universe page claims that the baryonic mass (ordinary matter) weighs at least $10^{53}$ kg Hence, with these datas, Dark matter weighs \$5.5 \times ...

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Could the universe really be expanding at a constant rate? Everything is possible I suppose, but the evidence suggests the universe is expanding at an accelerating rate, see Wikipedia. This came as something of a surprise in 1998. I was just thinking, sorry if this idea is idiotic, but since we know galaxies move away from each other at an ...

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The uncertainty principle is often confused with the observer effect. The former says that the certainty in position times the certainty in the momentum is greater than some constant. We think of momentum and position as two different things, but the underlying physical phenomenon may not be. Of course, none of this speaks to whether or not quantum ...

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Could the universe be accurately simulated with an infinitely powerful computer? First Could and infinitely powerful are not compatible. A system able to simulate / predict accurately anything is quite impossible : one would need a clone universe able to compute faster than the universe runs. Initial values, indistinguishability and uncertainty ...

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Any finite physical system can be simulated by a universal computer. This includes quantum systems, which could be simulated by a universal quantum computer if we knew how to build one. Quantum mechanics is deterministic in the sense that the state of the whole of physical reality at one time can be worked out from the state at an earlier time given the ...

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The entropy law can be (comically) reinterpreted like "equilibrium is a state of maximum possible disorder under given physical constraints". So... things keep getting worse until it's as bad as it can get. Intuitively, large entropy means that things look more or less the same (macroscopically) for many different microscopic realizations. When the system ...

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