The first stars in the Universe turn on at about 400 million years after the Big Bang. WMAP data reveals the era.

Was dark matter created with the Big Bang?

... be put together then there can exist things beyond our own universe and dark energy can be some kind of phenomenon that is related to stuff beyond our own universe. And so, once you have that, you could start to ... dark energy, maybe it is something that is outside our own universe that in some sense, you can say, exists ...

gravitational lensing

Is dark matter really there and how do we know?

... an antiparticle which we the positron, but a photon is its own antiparticle, it doesn’t have a different antiparticle. ...