Research centers?

Well, SUPPOSEDLY: it increases your capacity to do research. Each RC lets you do 12 more research/turn than you otherwise would, but you have to pay 12bc for it. However, because RC's and Academies are so expensive, and based on all the other quirks in the game, it wouldn't surprise me if they behave differently.

I'm no expert, but here's how I understand it:

Research centres produce research points, where are automatically spent on whatever research you are doing. The more labs you have, the more research points you can potentially produce. It does cost money to use those research points, though, so the more money you have allocated to research, the closer to your maximum research potential you will be.

It's the same with factories, too.

Here's a different way of saying the same thing just in case that didn't make sense (I found it a bit hard to read myself.)

Each RC gives you an additional 12 beakers per turn capacity. In order to use all that capacity, your Industrial Capacity slider and your Research Spending slider must both be at 100%. Otherwise, you're using just a fraction of the capacity.

So, for a mathmatical example, if you have 5 RCs, that gives you a total capacity of 60 beakers. If your spending is equally divided between Military, Social, and Research (33% each,) you'll actually be getting 60 x 33% = 20 beakers from those buildings.

There is no practical difference between having 5 research buildings on one planet and having 1 research building on each of five planets, UNLESS there are planetary or starbase bonuses that apply on one planet and not the others. In which case, you'd be better putting all of your research buildings there.

-Dewar

What is the difference of building research center in 1 planet other than on all planets?. I dont really understand what the research center does. does it speed up research?

Besides the starbase bonus like Dewwar mentioned, keep in mind that lab is points based while markets are % based. It doesn't matter that much if you have labs in 1 planet or 1 in every planet, it matters that you don't build 1 in every planet because you would benefit more from lots of markets in same place.

So you would get more money for building 4 market on a PQ 4 planet and 4 lab on another PQ 4 planet than you would if you build 2 market and 2 research lab on the two PQ 4 planet.

In the case where you get a % bonus to research, it would be nice to build lots of labs there. Some cases would be when you have an event that boost the research of the planet or technological capital.
Having a ring or bunch of starbases help, but it's not a definite call for lots of labs.