How is raisin bread like the big bang

All galaxies will see other galaxies moving away from them in an expanding universe unless the other galaxies are part of the same gravitationally bound group or cluster of galaxies. A rising loaf of raisin bread is a good visual model : each raisin will see all other raisins moving away from it as the loaf expands. One may also ask, how do they know the universe is expanding?

The space in between the galaxies is stretching! And the farther away a galaxy is the more space there is to stretch so the faster the galaxy appears to move away from us. Over the past half-century astronomers have observed many other facts about the universe that all point to the fact that the universe is expanding.

Galaxies can not move in the direction perpendicular to the plane of the galaxy. They move in any direction as if they are a Frisbee. They all move like a flat disk in the direction of their flat plane.

Our Solar system also dose the same thing. Although the expansion of the universe gradually slowed down as the matter in the universe pulled on itself via gravity, about 5 or 6 billion years after the Big Bang, according to NASA, a mysterious force now called dark energy began speeding up the expansion of the universe again, a phenomenon that continues today.

Asked by: Reimundo Boeckmann science space and astronomy How is the universe like rising raisin bread dough? Last Updated: 9th April, One famous analogy to explain the expanding universe is imagining the universe like a loaf of raisin bread dough. As the bread rises and expands, the raisins move farther away from each other, but they are still stuck in the dough. Oussama Russo Professional. What is outside the universe? Jema Guereca Professional.

What is dark energy in the universe? Dark Energy is a hypothetical form of energy that exerts a negative, repulsive pressure, behaving like the opposite of gravity. The other dominant contributor is Dark Matter, and a small amount is due to atoms or baryonic matter. Bertila Incenso Professional. Why is space expanding? Cosmological redshifts result from the expansion of space and the light moving through that space between us and a distant galaxy or quasar.

Space is expanding everywhere, so the more distant an object is, the more rapidly it appears to be moving away. Sofiane Ramalheira Explainer. How fast is the universe moving? It covers this route at a speed of nearly 30 kilometers per second, or 67, miles per hour. In addition, our solar system--Earth and all--whirls around the center of our galaxy at some kilometers per second, or , miles per hour.

Why are galaxies so far apart? It only takes a minute to sign up. Connect and share knowledge within a single location that is structured and easy to search.

The answer to the question here Did the Big Bang happen at a point? The answer RonMaimon provided to this question Does it make sense to say that the universe has a center? All of these answers center around a single concept: that the universe appears to be expanding away from every known point, and that all points can be conceived as the center of the universe. I've seen many references to a loaf of raisin bread, where no matter which raisin you are on the inside of the bread, all other raisins are expanding away from you.

However, those all rely on the idea that because the universe appears to be expanding equally away from all known points we are assuming that our tiny view of the universe is indicative of the whole. How can we be certain that there is not an initial point of origin, and that all galaxies are not moving away from one another for the same reason that pellets from a shotgun all move away from each other after leaving the barrel? Could not we attribute this equal expansion the result of a blast that provided momentum in one direction, with all known galaxies spreading out as they move laterally?

That would provide the expansion as we currently witness it, while still allowing for an origin. We cannot be certain, but the fact that the galaxies are all moving away from each other is not the key observation in this context.

The key observation is that the universe is isotropic on large scales. Since we observe large scale isotropy and homogeneity the simplest assumption one that is based on evidence is that the universe really is isotropic and homogenous. Any other model will require an unjustified assumption of some conspiratorial effect that acts to hide the true asymmetry. That conspiratorial assumption one that is not based on evidence will add complexity to the model but will not increase predictive power.

If there were an actual center then galaxies away from the center would not see an isotropic universe. Instead they would see fewer galaxies in one direction than in the other. Given the trillions of galaxies we see, it would be highly unlikely that ours just happened to be the one in the center.

Of course, there are other possible explanations for the observed isotropy. One is that we are in the center, that is unlikely but does not require any additional explanation. Another is that we are not in the center but we can see only a small portion of the universe that is isotropic.

That requires an explanation about why we can only see a small portion. All in all, the homogenous and isotropic assumption is the simplest one that explains our homogenous and isotropic observations. So until we have some observations that contradict it, we will use it. There would literally be no reason to use another until such evidence is discovered.

We know that the expansion of the Universe is accelerating and we can measure this. The true process of accelerating expansion is best modeled by the Friedmann equations , a solution of General relativity.

The unique success of these models in describing the observed evolution of the Universe is why we explain the Universe using these models. Skip to navigation Skip to main content. Edwin Hubble proposed the raisin pudding analogy which helps us to mentally picture how Hubble's Law relates to an expanding universe. Consider a loaf of raisin pudding or bread dough baking in an oven, with raisins sprinkled evenly throughout.