Recent content by Daniel Batt

The original query is an interesting question, that has no doubt been pondered for thousands of years, well before physics turned up. Martin Luther's response, when asked what happened before creation, was to say God was making sticks to hit people with who asked such impertinent questions...

This article from HuffPo suggests a much greater impact of it going supernova. "Dr. Brad Carter, Senior Lecturer of Physics at the University of Southern Queensland, outlined the scenario to news.com.au. Betelgeuse, one of the night sky's brightest stars, is losing mass, indicating it is...

OK, thanks, everyone for your combined learning and wisdom. I didn't think to look for an online red shift calculator. And, yes, I obviously am a victim of taking popularisers too literally (or misunderstanding them). Wonderful links. Thanks again!

"We cannot know what it is like 'today', as the photons need to take AT LEAST 12 billion years to reach us!" Well, yes, I imagine there is a lot we don't know about what the last 12 billion years has done to that galaxy, but we do know, at the very least, that the velocity between us and the...

OK, I am brave enough to risk sounding like some kid who doesn't get secondary physics, let alone tertiary physics, with this question, but please bare with me. Given galaxies at the edge of the horizon of our universe appear to be accelerating away from us at greater velocities, surely we...

Okay, I know this is an old thread, but, if given a choice between and electron and a proton, it had to be a proton, because if it were an electron, we would have to add a few more .99's to the speed of light it was travelling. While Utah were looking for cosmic rays, I don't see why it had...

Okay, thanks. So a neutron star can only accelerate mass toward its centre of gravity at well below c, whereas a black hole accelerate mass to almost c before the event horizon. This means that angular momentum increases the speed of mass even higher, as it is moved by magnetism up toward the...

Thanks, I thought that was what was going on, like a reverse of the northern lights. But a neutron star doesn't have enough gravity, or the accretion disc's energy, to create a similar energy beam on the pole of the star?

Can anyone point me to a journal article that describes, mathematically or otherwise, how those jets shoot from the poles of some black holes with accretion discs and AGN. Also, if you will forgive the additional question, is there any reason why the physics that describe the ejection from...