How can the universe not have a center?

1.76K viewsOtherPhysics

If I understand the big bang theory correctly our whole universe was in a hot dense state. And then suddenly, rapid expansion happened where everything expanded outwards presumably from the singularity. We know for a fact that the universe is expaning and has been expanding since it began. So, theoretically if we go backwards in time things were closer together. The more further back we go, the more closer together things were. We should eventually reach a point where everything was one, or where everything was none (depending on how you look at it). This point should be the center of the universe since everything expanded from it. But after doing a bit of research I have discovered that there is no center to the universe. Please explain to me how this is possible.

Thank you!

In: Physics

50 Answers

Anonymous 0 Comments

Someone once asked this in a Physics III course I took in college and I loved the professor’s response:

>The line of the equator is defined via a metric: the mid-distance between both North and South poles.

>The poles are defined by physical circumstance: they’re the two spots on the Earth where it’s rotational motion does not cause angular displacement.

>The Prime Meridian is defined by coincidence: It’s the line that passes through both poles and an observatory located in Greenwich, UK. That town could have been placed anywhere. Nobility argued it should run through London, Paris, and other locations instead of where it is today.

>Null Island (0N, 0E) is a buoy that was installed where the Prime Meridian and Equator intersect. Most terestrial navigation measurements use this as the origin, the “center of the map” if you will. And yet, it is still coincidentally located way off the coast of Africa because of the arbitrary definition of the Prime Meridian.

>Suppose an alien craft parks 10 light minutes above the planetary plane (the imaginary disk that all the planets seem to be locked to). Where do you think they’ll decide to put the “center of the map”? Should their algorithms for navigation be sensitive should they pick a different location? Of course not.

>There are two possibilities: (1) The universe is finite. In that case, we can also prove that it needs to loop around itself much like the surface of a sphere, like the surface of the Earth. or (2) The universe is infinite. In that case putting “the center” anywhere doesn’t matter because we’re just measuring things *relative* to whatever arbitrary origin we use, just like in Case 1. Either way, we have a “centerless” metric space.

QEDMF

You are viewing 1 out of 50 answers, click here to view all answers.