• Re: Is the universe infinite, or does it have a limit?

    From Jan Panteltje@alien@comet.invalid to sci.astro,sci.electronics.design,sci.physics on Sat Feb 7 03:50:40 2026
    From Newsgroup: sci.physics

    Martin Brown <'''newspam'''@nonad.co.uk>wrote:
    On 05/02/2026 16:59, Jan Panteltje wrote:
    Martin Brown <'''newspam'''@nonad.co.uk>wrote:
    On 05/02/2026 06:23, Jan Panteltje wrote:
    Thomas 'PointedEars' Lahn <PointedEars@web.de>wrote:
    However, our universe is expanding, and there are points whose distance from
    each other increases faster than light could propagate between them. So >>>>> even if our universe would be closed, it would not be possible for light to
    arrive at its point of emission by going around our universe. Maybe that is
    the reason why this has never been observed.

    Just a simple question, I am no astrofishycist,
    is that 'expansion' we observe deduced from the red shifts we measure? >>>> Or brightness of some stars?

    Actually both. Redshifts give the most reliable data at cosmological
    distances and you can see all the clouds of neutral hydrogen along the
    like of sight if you find a suitably bright remote quasar. The so-called >>> Lyman forest of absorption lines.

    https://en.wikipedia.org/wiki/Lyman-alpha_forest

    In addition there are also certain stars like a particular class of
    supernova type IA that due to how they arise go bang at more or less
    exactly the same total mass every time and so from the lightcurve and
    it's peak brightness you can work out how far away it is. The brightest
    of the standard candles these supernovae can outshine their entire host
    galaxy for a couple of weeks. Catching them early helps astrophysicists
    pin them down and amateur supernova surveys with CCD cameras assist.

    https://science.nasa.gov/mission/roman-space-telescope/type-ia-supernovae/ >>>
    New professional hardware is coming online to speed discovery up.

    There is no way for us to know if the universe itself is infinite or
    just very very big. There is always going to be a finite limit to the
    region that we can ever know about (ignoring for the moment that at the
    greatest distances it is an optically opaque hot plasma now seen as the
    4K microwave background radiation.

    How about tired light theory (light slowing down causing redshift)?

    Doesn't really hack it at all. Pauli's phrase "Not even wrong" is
    probably the kindest description for Le Sage Theory.

    https://en.wikipedia.org/wiki/Not_even_wrong

    Sure, but motivate it
    Today (and my hat of to German science teaching TV channels!) there was a lecture' about 'quantum' in physics on zdfinfo.de
    program named Terra X presented by Harald Lesch (professor).
    And that is what I am missing on UK free to air TV, most there is braindead, games and repeats of old movies.
    Now if they also kill social media for people younger than 16 like they do down under, end of the world...
    Anyways, it went among other things into light as wave versus light as particle, the 2 slit experiment, and quantum secure
    communication,
    a view at the experiments, visiting the labs etc etc..
    Now if you see light as a wave, then its speed depends on the medium.

    The speed of light in a *vacuum* is a fundamental invariant for physics >proved by Maxwell from his equations of electromagnetism well before >Einstein had conceived of relativity. It was a surprise at the time.

    It is one of the things that catches out experimenters measuring the
    speed of light - imperfect vacuum in the apparatus has to be corrected
    for. Even the best man-made hard vacuum is poor compared to near space.

    The systematic correction is small but for a period was applied by a
    highly respected experimenter in the wrong sense. People who duplicated
    the setup also made the same error. It was only noticed when a new
    method came available with better precision and a harder vacuum that the >mistake was discovered. Speed of light with error bars as a function of
    time and method employed makes for an interesting graph.

    Consensus these days is that the universe is not empty, talk about dark matter (or Le Sage particles in my take)
    would mean that light speed can vary depending on the density of the medium, >> Jeroen from CERN had pointed to a paper that shows the universe filled with a fluid makes most math for elementary particles
    as we know it work.

    There is no need for a cosmic ether.
    Michelson-Morely null result put paid to that idea a long time ago.

    There is a sea of virtual particles flipping into and out of existence
    on borrowed energy as can be demonstrated by the Casimir effect.

    Epicycles was good math but the planets do orbit the sun...
    Makes it all (sort of) simple..

    Epicycles were the Fourier transform method of their day. They worked
    well enough to enable practitioners to do what they needed to do.

    Eventually better observational constraints and new theories come along
    that can improve upon the established methods of the day. Back when
    Galileo was around the Jesuit astronomers were happy enough to use
    heretical heliocentric solutions in private because they worked.

    Even now the most accurate planetary ephemeris is computed using
    symbolic expansions of the perturbations of every planet on every other.
    It all gets very messy in the real world even with just 9 planets.

    You need a *mechanism* to explain and predict things!! New things!!!

    Unless your theory has predictive powers and predicts something new that
    can be experimentally verified or used to refute it then it isn't a >scientific theory it is just random word salad pseudoscience.

    Le Sage predicts that the 'noise' in the speed of a clock close to earth is bigger
    than in 'free' space.
    I mentioned that here several times.
    We get ever better clocks, that noise should be measured in space and on earth. It predicts a lot more things, like (and that is enen used as argument against it)
    the internal heating of planets.
    Now usually, without any evidence! attributed to 'nuclear processes'.

    If EM radiation is a state of Le Sage particles all becomes logic and very simple.
    'state' is an interesting thing, spin? new particles formed by the combination of those Le Sage particles with electrons?
    And the big question is : Where do these Le Sage particles come from.
    We are just ants in a garden, what those call their 'Universe' is limited
    so is our view.
    Maybe as many 'bangs' as water molecules in the ocean exists.
    Brain limitations or unwillingness to 'see', religions used
    to control people and suck their money - will not find truth
    Einstein admitted he failed to connect gravity and light
    I just gave a glimpse
    It is easy
    You earthlings only need to drop Albert's brain crap.
    And be free!
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