Aarav Sangar said:How can the universe keep on expanding if it's infinite? Expanding metal, like a cube of aluminium, has a surface area which forms a border for the matter contained inside. So the universe must have a border for the matter it contains.
While the universe may be expanding infinitely, it does not necessarily mean it has no edge. The concept of an infinite universe means that it has no definite boundary or limit, but it could still have a finite size. It is similar to how we can keep counting numbers infinitely, but there is no single largest number.
The universe is not expanding into anything. It is expanding within itself. The expansion of the universe refers to the increase in distance between galaxies and other celestial bodies, not the expansion into new empty space.
Scientists have observed the redshift of light from distant galaxies, which is a result of the expansion of the universe. This means that the wavelengths of the light have stretched as the galaxies move away from us at increasing speeds. Additionally, the cosmic microwave background radiation, which is a remnant of the Big Bang, provides further evidence of the expansion of the universe.
It is currently unknown whether the expansion of the universe will ever stop. The rate of expansion is determined by the amount of matter and energy in the universe, and we do not have enough data to accurately predict what will happen in the future. Some theories suggest that the expansion could eventually slow down and reverse, leading to a "Big Crunch" where the universe collapses in on itself.
The expansion of the universe does not have a significant impact on us on Earth. The expansion is happening at a very large scale and is not noticeable in our daily lives. However, the expansion does play a role in the formation and movement of galaxies, and it could potentially affect the fate of the universe in the distant future.