Dark energy is just the difference in energy caused by the expansion of the universe, which we observe with telescopes by objects getting further away from us over time (a great analogy by Brian Cox is that if you put a raw bun (dough) with sesame seeds in the oven, as it expands the sesame seeds will become further apart, this is an analogue to what happens to galaxies, star systems, even planets to a much smaller degree as the universe expands.
Dark Matter is also observed through it's Gravitational Lensing affects and the affect of Dark Matter-Matter annihilations on the cosmic microwave background.
All in all, sometimes it can be difficult to imagine these things, and you could even be right, there might be no such thing and what we observe could be a completely different phenomenon, but as of right now our observations of the X-Ray background and the lensing effects have no other reasonable scientific explanation and until we have the capability to directly measure their affects on objects we are stuck half-way between hypothesis and theory :P
Dark matter may actually not be there. Modified gravity models are still well alive. More data will tell us, soon, hopefully, which hypothesis is right and which hypothesis is wrong :)
I've read all of the explanations.
I don't buy it...
I'm not convinced that the Universe is expanding....
just because there is 'no reasonable explanation' doesn't mean the current explanation is correct.
It just means there is a failure of imagination.
Dark energy is just the difference in energy caused by the expansion of the universe, which we observe with telescopes by objects getting further away from us over time (a great analogy by Brian Cox is that if you put a raw bun (dough) with sesame seeds in the oven, as it expands the sesame seeds will become further apart, this is an analogue to what happens to galaxies, star systems, even planets to a much smaller degree as the universe expands.
Dark Matter is also observed through it's Gravitational Lensing affects and the affect of Dark Matter-Matter annihilations on the cosmic microwave background.
All in all, sometimes it can be difficult to imagine these things, and you could even be right, there might be no such thing and what we observe could be a completely different phenomenon, but as of right now our observations of the X-Ray background and the lensing effects have no other reasonable scientific explanation and until we have the capability to directly measure their affects on objects we are stuck half-way between hypothesis and theory :P
Dark matter may actually not be there. Modified gravity models are still well alive. More data will tell us, soon, hopefully, which hypothesis is right and which hypothesis is wrong :)
I've read all of the explanations.
I don't buy it...
I'm not convinced that the Universe is expanding....
just because there is 'no reasonable explanation' doesn't mean the current explanation is correct.
It just means there is a failure of imagination.
NOTE: plate tectonics was silly...until it wasn't
Watch out he might flag your stuff if you prove him wrong.