Where does the universe expand whether it is already infinite?

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Where does the universe expand whether it is already infinite? – Mael, age 10, Missoula, Montana

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If you might be baking a loaf of bread or several muffins, pour the dough right into a mold. As the dough bakes within the oven, it expands within the baking pan. Any chocolate chips or blueberries within the muffin batter will turn into further apart because the muffin batter expands.

The expansion of the universe is comparable in some ways. But this analogy gets one thing unsuitable: While the dough expands into the baking pan, the universe has nowhere to expand to. It just expands into itself.

It can feel like a brain teaser, however the universe is viewed as all the pieces throughout the universe. There isn’t any pan within the expanding universe. Just dough. Even if there was a pan, it will be a part of the universe and subsequently would expand with the pan.

Even for me, a Teaching professor for physics and astronomy For someone who has studied the universe for years, these ideas are obscure. You don't experience something like that in on a regular basis life. It's like asking which direction is further north of the North Pole.

Another approach to think concerning the expansion of the universe is to take into consideration how other galaxies are moving away from our galaxy, the Milky Way. Scientists know the universe is expanding because they will track other galaxies as they move away from ours. They define expansion by the speed at which other galaxies are moving away from us. This definition allows them to assume expansion while not having something to expand into.

The expanding universe

The universe began with the Big Bang 13.8 billion years ago. The Big Bang describes the origin of the universe as a particularly dense, hot singularity. This tiny point suddenly experienced a rapid expansion called inflation, by which every place within the universe expanded outward. But the name Big Bang is misleading. It wasn't an enormous explosion because the name suggests, but moderately a time when the universe was rapidly expanding.

The universe then rapidly condensed, cooled, and started producing matter and light-weight. Eventually it evolved into what we all know today as our universe.

The concept that our universe was not static and will expand or contract was first published by physicist Alexander Friedman in 1922. He mathematically confirmed that the universe is expanding.

While Friedman proved that the universe was expanding at the very least in some places, it was Edwin Hubble who delved deeper into the speed of expansion. Many other scientists confirmed that other galaxies are moving away from the Milky Way, but in 1929 Hubble published his famous work This confirmed that your complete universe is expanding and that the speed at which it’s expanding is increasing.

This discovery continues to puzzle astrophysicists. What phenomenon allows the universe to beat gravity and hold it together while concurrently expanding by pulling objects within the universe apart? And what's more, the speed of expansion increases over time.

Many scientists use a picture called an expansion funnel to explain how the expansion of the universe has accelerated for the reason that Big Bang. Imagine a deep funnel with a large rim. The left side of the funnel – the narrow end – represents the start of the universe. As you progress to the proper, you progress forward in time. Cone expansion represents the expansion of the universe.

Scientists haven’t been capable of directly measure where the energy causing this accelerated expansion comes from. They couldn't detect it or measure it. Because they will't see or directly measure this sort of energy, they call it dark energy.

According to the researchers' models, dark energy have to be essentially the most widespread type of energy within the universe, accounting for around 100% 68% of all energy within the universe. The energy from on a regular basis matter that makes up the Earth, the Sun, and all the pieces we see makes up only about 5% of the full energy.

Outside the expansion funnel

So what’s outside the expansion funnel?

Scientists haven’t any evidence of anything outside our known universe. However, some predict that there could possibly be multiple universes. A model that spans multiple universes could solve among the problems scientists are encountering with current models of our universe.

This is an enormous problem with our current physics Researchers cannot integrate Quantum mechanicswhich describes how physics works on a really small scale, and gravity, which governs physics on a big scale.

The rules governing the behavior of matter at small scales depend upon probability and quantized or fixed amounts of energy. On this scale, objects can emerge and disappear again. Matter can behave like a wave. The quantum world could be very different from the way in which we see the world.

On a big scale, as physicists call it classic mechanicsObjects behave as we expect them to in on a regular basis life. Objects usually are not quantized and might have continuous amounts of energy. Objects don’t appear or disappear.

The quantum world behaves like a light-weight switch where energy can only be turned on and off. The world we see and interact with acts like a dimmer switch, allowing for all levels of energy.

But researchers run into problems when they struggle to review gravity on the quantum level. On a small scale, physicists would should assume that gravity is quantized. But the research that lots of them have conducted doesn’t support this concept.

One approach to bring these theories together is that this Multiverse theory. There are many theories that look beyond our current universe to elucidate how gravity and the quantum world work together. Leading theories include: String theory, Brane cosmology, Loop quantum theory and lots of others.

Regardless, the universe will proceed to expand, with the gap between the Milky Way and most other galaxies increasing over time.

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