If our universe is a balloon with galaxies on the surface, what is inside the balloon?

Answer 1

Hi Skycat -

The balloon analogy is intended to represent our normal three-dimensional universe as a two-dimensional membrane - that is, the universe that we know is entirely contained within the surface of the balloon - like the old stories about Flatland or Lineland. This means that to the limits of our perception, there is no center to the expansion, but if we look out in any direction ALONG THE SURFACE (which is the only way we can look), then we will see the galaxies receding. The sticky part of this analogy is that we cannot perceive a dimension perpendicular to the three we already have, so we cannot see the center. It's really just meant as a thought experiment to help visualize the problem, not as a physical reality.

Answer 2

Galaxies and everything else in the universe are *not* on the surface of the universe. Everything in the universe is just that...*in* the universe.

Have you maybe gone off in the wrong direction by seeing the familiar analogy of a balloon to the universe?

Answer 3

Jolly good question,
I have always described our expanding universe to kids by drawing a few dots on a flat balloon with biro, then blowing it up. You raise a question in my mind as to what then happens to the gas inside.
Then I espied, or realised that that is the whole nature of gravitational force. You need an "empty" space to slow the expansion, and draw it all bak to a chuck in the bin
Matter attracts matter, that is why this keyboard isn't floating around.
knackered balloon. Well.
Not exactly the full story, but it explains it to kids, as long as you remind them that this will not happen for many billions of years.

All the bast with the uni
Bob

Answer 4

A majority of cosmologists believe that the observable universe is an extremely tiny part of the whole universe and that it is impossible to observe the whole of comoving space. It is presently unknown if this is correct, and remains under debate. According to studies of the shape of the Universe, it is possible that the observable universe is of nearly the same size as the whole of space. If a version of the cosmic inflation scenario is correct, then there is no known way to determine if the whole universe is finite or infinite. If it is infinite, the observable Universe is just a tiny speck of the whole universe.The currently observable universe appears to have a geometrically flat space-time containing the equivalent mass-energy density of 9.9 × 10-30 grams per cubic centimetre. This mass-energy appears to consist of 73% dark energy, 23% cold dark matter and 4% atoms. Thus the density of atoms is on the order of a single hydrogen nucleus (or atom) for every four cubic meters of volume. The exact nature of dark energy and cold dark matter remain a mystery.During the early phases of the big bang, equal amounts of matter and antimatter were formed. However, through a CP-violation, physical processes resulted in an asymmetry in the amount of matter as compared to anti-matter. This asymmetry explains the amount of residual matter found in the universe today, as nearly all the matter and anti-matter would otherwise have annihilated each other when they came into contact.Prior to the formation of the first stars, the chemical composition of the Universe consisted primarily of hydrogen (75% of total mass), with a lesser amount of helium-4 (4He) (24% of total mass) and trace amounts of the isotopes deuterium (2H), helium-3 (3He) and lithium (7Li).[15][16] Subsequently the interstellar medium within galaxies has been steadily enriched by heavier elements. These are introduced as a result of supernova explosions, stellar winds and the expulsion of the outer envelope of evolved stars.[17]

The big bang left behind a background flux of photons and neutrinos. The temperature of the background radiation has steadily decreased as the universe expands, and now primarily consists of microwave energy equivalent to a temperature of 2.725 K. The neutrino background is not observable with present-day technology, but is theorized to have a density of about 150 neutrinos per cubic centimetre.

Answer 5

Each entity in the universe is isolated from every other by time.
Looking at a person in the same room with you,you are seeing that person as they existed billionths of a second in the past.
The universe would be expanding as a two dimensional disc.
The universe injects a holographic aspect to allow interaction as though no isolation exists,so the universe expands as though it was a solid sphere

Answer 6

Well, your analogy is wrong and you are mistaken. The galaxies are IN the "balloon" and also on the surface.

Answer 7

raging energies

but even more importantly, what's outside the balloon?

cant just be nothing can there, which would also mean the universe is in fact finite in space and there is an end to it

Answer 8

If it does not contain mass inside the Baloon per your inquiry , then it certainly could not be a vaccum.
It must be a hole which contains the Bulk of the Substance of space.

Answer 9

The centre of the Universe and the point from which we all came

Answer 10

Maybe space...maybe another universe. Nobody knows for sure.