World Science Scholars

2.6 A Brief History of the Universe

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    • From Earth, we can see cosmic background radiation with the same properties at the same distance in every direction—what is referred to in this Master Class as the “plasma screen.” Does this mean Earth is at the center of our universe? If not, where is the “center?” Did the universe have a single starting point? Explain your answer.

    • Earth is not the center. Just like a chocolate chip on a muffin, everything is expanding away from it from its perspective. The universe did have a starting point if you be think of how everything is expanding and if time runs backward, it would eventually go back to a point.

    • Starting point yes.
      Standing in any planet or star you can look up and it will appear as if you are in the center because of how uniform the universe is. There is no center.

    • Earth is not the center. Each point, star, planet, and galaxy could be considered the center of the universe. There essentially is not a single center of the universe, since space is expanding relatively.

    • The answer is both yes and no. Any point in the universe can claim to be the “center” of its observational bubble (of its observable universe), but neither point is actually “the center of the universe” as a whole, just like no point on the surface of the Earth is “the center of the surface of the Earth”. The reason is that the Big Bang is not a point in space but a moment in time.

    • The Cosmic Background Radiation (CBR) is presented in many of the presentations as an expanding shell surrounding the known universe as if it were a shock wave from the Big-Bang. If this were so, then it would imply an “edge” to the universe and therefore a “center” could then be defined. CBR actually permeates all of the observable universe as residual energy left over from the Big-Bang. Since there is no definable “edge” to the universe, there can’t be a definitive “center”.

    • There is NO center, and CBR looks the same from any viewpoint in the universe, though this is not intuitive. Even though I like the explanation of the rising muffin with the chocolate chips (or raisins for Brian Greene), this metaphor would imply that there is a center of the muffin with maybe a raisin sitting in the center. This is where the metaphor fails, and to my mind we will never find a better one as the concept of ´no edge´ is simply – at least for me – not imaginable. For me, there is always the lurking question: OK, no edge, but then what is beyond (the edge)?

    • No edge because of the cosmological constant and therefore no middle.

    • Every point in this universe could be considered at the center of our universe.

    • If the Big Bang started at singularity then every place in the current universe is at the center of the universe.

    • Ladies and Gentlemen,

      Earth isn`t at the center of the universe.

      When we see the plasma screen of the edge of the universe, this shows a hydrogen limit on the edge of the universe.

      In different ages, different tech levels allow a bigger picture.

      Currently the picture has levels of planetary, solar, stellar, Milky Way galaxy, local cluster and Virgo Super cluster.

    • so again it comes down to what we can see, so until we view farther this is all we accept.

    • The earth is not a starting point, and i believe that the universe has a starting point, from which it expands

    • earth is nothing in universe…

    • No centre but there must have been a starting point.

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