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Total Mass of the Universe

  1. May 24, 2004 #1
    Have cosmologists determined the total mass of the universe?
  2. jcsd
  3. May 24, 2004 #2


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    Mass is the resistance of some physical object to momentum changes.

    It means that we have to know the total resistance of our universe to momentum changes from the Big-Bang until now.

    But maybe not the total answer is important, because if space/time dynamical structure has a fractal-like shape then some butterfly-effect can change very quickly the "character" of the universe.
    Last edited: May 24, 2004
  4. May 25, 2004 #3
    there is no way to ever measure the mass of the universe

    since even it's limits are unknown

    it's like asking how many demons will fit on the head of a pin

    even the mass of the visible universe (which is not the whole universe) can never be acurately measured

    if the universe is infinite then the total mass of the universe = infinity (exactly)
    Last edited: May 25, 2004
  5. May 25, 2004 #4
    btw. the question of what is the total size of the universe can never be answered either :smile:
    Last edited: May 25, 2004
  6. May 25, 2004 #5
    But in general theory of relativity, it is crucial that we know the total mass of the universe in term of its density for the values of omega.
  7. May 25, 2004 #6
    The mass of the universe will be known accurately when the dark energy dark matter
    problem is sorted and gravity quantised to the planck length.Then we will have an accurate theory of gravity that will allow us to use experimental data to calculate the mass of the universe.
  8. May 25, 2004 #7
    sure we will :wink:
  9. May 25, 2004 #8
    Well, you sure are a confident SOB given what I suspect is quite a limited education. If you believe in the "big Bang" and relativity (which I assure you is valid) then the "whole universe" is the "visible universe". Now I will admit that we now know of no way to measure it accurately but the assumption that such a thing can [size="+1"]never[/size] be done is a rather extreme statement.

    For your edification, go take a look at


    Have great fun -- Dick
    Last edited: May 25, 2004
  10. May 25, 2004 #9
    and this coming from a guy called 'Dr. Dick" ???

    I earned my MS Degree in Electronic Engineering - with emphasis in semiconductor physics

    I've also studied a broad range of sciences through the past 20 years
    including cosmology - with emphasis on BBT and Superstring Theory

    what's your degree in?
  11. May 25, 2004 #10
    Boy, am I impressed!!!

    Have fun -- Dick
  12. May 25, 2004 #11

    I had no idea the Supreme Being was named DoctorDick

    what is it like having omnipotent knowledge of the universe?

    first of all anyone who claims to KNOW anything about the universe is a crackpot

    even George Gamow (co creator of BBT) never claimed to have absolute knowledge of the cosmos

    he simply developed a theory based on the work of Alexander Friedmann and George Lemaitre - which was supported by the discovery of stellar redshift by Edwin Hubble in 1929 and finally the discovery of CMBR in 1963 by Arno Penzias and Robert Wilson

    BBT is not the theory to end all theories - there are very many unanswered questions, and many other interpretations of CMBR and redshift

    any number of ad-hoc theories could be developed from the same data
    including infinite steady state models

    who the hell are you to assure anyone of anything?
  13. May 25, 2004 #12
    the only thing human beings can ever be sure of KNOWING is that nothing is KNOWABLE

    everything in human experience is either perceived or imagined
  14. May 26, 2004 #13

    Does reality has its own independent existence? If you say yes then you are just like what Einstein used to believe when he was pondering the mystery of the universe.
  15. May 26, 2004 #14
    yes, I do very strongly believe that reality has it's own independent existence

    in my opinion, human exploration and discovery are completely subjective to human perception and philosophy - but these perceptions and philosophies never alter true reality, but only perceived reality

    Einstein was very good at asking the right questions, and never hesitated to use intuition as an instrument of exploration
  16. May 26, 2004 #15
    But if yo want to calculate the mass of the observable universe...
    perhaps you can do a gross estimation; for example, the mass of the Virgo supercluster is estimated to be around 1015 solar masses
    Virgo supercluster seems a standard sized supercluster. Then suming this mass for all the total known superclusters... The estonian Einasto published a catalogue of superclusters some time ago, but I'm not sure if more superclusters have been discovered since the publication of the catalogue. And I don't know also the mass of the voids, the huge voids between superclusters. Anyway don't seem that the voids have to have very much mass. I will try to look tomorrow to all these things and I will give my estimation of the mass of the observable universe

    PS: Thid spage gives for the Great Attractor, the famous supercluster in direction our galaxy cluster is heading to, of 5*1016 solar masses
    BTW, voids take up about 98% of the volume of the universe, according to this other webpage
    This article of nature says that voids contains approximately the 20% of the total mass of the universe
    Last edited: May 27, 2004
  17. May 26, 2004 #16
    by current cosmology about 99% of the mass of the visible universe is unaccounted for (i.e. invisible) dark matter was invented (theorized) to make up for the missing mass

    it's anyone's guess if dark matter exists, if the visible universe is 1% of the total universe, or just one of infinite regions in a boundless universe

    how can we ever know?

    the fastest propulsion system we've got is only capable of 0.0027% c on a good day

    at this velocity (8000 m/s) it would take 37475 years to travel 1 lightyear
    (1 lightyear = 9 460 730 472 580 800 m)

    if the visible universe is 20 000 000 000 lightyears across
    it would take 749 496 535 072 588 years to travel it's diametre
    or 374 748 267 536 294 years to travel it's radius
    assuming we were at it's centre, which is highly unlikely

    just so that we could get a view of the next visible universe 20 000 000 000 lightyears further distant

    who has that much spare time? just to validate a theory
  18. May 28, 2004 #17
    I need help
    Given that the radius of the observable universe is 47 billion of light years(that is, our particle horizon is 47 billions ly away in proper distance), then the volume of the observable universe is: 4/3*pi*r3=434672 billion of ly3
    Given that cosmic voids occupy an 98% of the universe, then the total volume of the cosmic voids in the observable universe is 434672*98/100=425978 billion ly3

    But i need to find the volume of the Virgo supercluster to keep on with the calculations, but i'm having a hard time tryng to find it. Anyone knows the volume of the Virgo supercluster?
    Last edited: May 28, 2004
  19. May 28, 2004 #18

    The following extract from Yahoo search engine when I typed in "Size of Virgo supercluster."

    The nearest large scale structure or arrangement of galaxies found is the Local Virgo Supercluster of galaxies, centered at z = 0.004 ( 24 Mpc) and extending all the way to us (overall size ~ 50 Mpc). To study the Virgo supercluster, a Virgo-centered supercluster coordinate system has been proposed (see Appendix in Vallée, 1991c), improving on the earlier system of de Vaucouleur.
  20. May 29, 2004 #19
    The bad news is that i'm still unable to determine the volume of the Virgo supercluster. The Virgo supercluster (aka local supercluster or Coma-Virgo supercluster) has a pancake shape, with a diameter of 200 million of ly, but i'm unable to find the height of the pancake. I'm unable to find the height of the cylinder.
    The good news is that this article
    says that an experiment performed by the balloon-borne telescope Boomerang estimated that the mass of the visible universe is of 100 trillion, trillion, trillion, trillion tonnes
  21. May 31, 2004 #20

    according to Big Bang Theorists, the visible universe is 13 000 000 000 years old

    so it's radius would be 13 000 000 000 lightyears since the light would require that much time to travel from it's point of origin

    when you use the term 'Billion' i presume you mean an American Billion (1 000 000 000)

    a European Billion is 1 000 000 000 000 (1 million squared)
    1000 Million is called a Milliard

    so the visible universe is 13 Milliard lightyears radius, according to BBT
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