The historian in me says I'm an atheist. The scientist in me says I'm agnostic. Because the idea of an omnipotent being is unfalsifiable - science cannot prove or disprove its existence. In other words it's not even a valid scientific thing to consider but we can't say either way and always have to be open to evidence that would prove god's existence.
Outside the realm of our 4 dimensions is merely speculation and beyond the realm of solid science. I also teach math and though I'm not an expert, multiple dimensions is merely a way of mathematically understanding things without the need to have it directly relate to the real world. In other words there's no use even talking about it from a scientific or reality way. Just because something could possibly be real doesn't mean there is currently any scientific evidence to suggest god does exist. In fact there is no scientific evidence to suggest god's existence. Again, the idea of god is unfalsifiable.
I don't believe in climate change. Believe means (to me) to accept something without evidence. For example people believe in god without the need for evidence beyond personal experience and maybe a book written over a thousand years ago. I accept climate change is real or extremely likely to be so based on the plethora of evidence provided by climate scientists and though I've only read a few complete books on the topic and a number of articles so I'm in no way an expert, I accept the scientific community's consensus on the topic.
How specifically did Krauss silence those he disagreed with? You didn't provide an example.
In the scientific community in general if you want to override the overwhelming concensus then the onus of overriding all of the evidence has to be very high indeed. If you want to overturn the general understanding of physics for example you had better have a crap load of evidence to prove they are wrong. The same can be said for paranomal claims. Since they have no credible scientific evidence to back them you'd be making an extraordinary claim if for example you said someone had telikinetic abilities, could talk to the dead or could see into the future. Extraordinary claims require extraordinary evidence. Scientists should consider listening to counter evidence to their theory but they don't have to waste their time trying to discredit every one who says they've created a perpetual motion machine that violates the second law of thermodynamics. Nor should an evolutionary biologist give the time of day to a creationist who wants to have a debate. Some things have been thoroughly debunked and without some serious new evidence being brought to the table, there's really no need to waste time listening to a crank or dogmatic religious fanatic. None of this is focused on your criticism of Krauss directly because I haven't yet heard the specific thing he said or did.
Science is in fact majority rules. That's not to say that the minority cannot be right but more often than not the majority is correct. Yes I spent my time in university doing my masters degree and studying Kuhn and Popper and scientific revolutions. The bottom line is still that extraordinary claims require extraordinary evidence and the minority hadn't yet provided sufficient evidence. Yeah we can discuss numerous examples like Alfred Wagner's ideas about continental drift or plate tectonics but again once he had enough evidence to show the scientific community had to change their view. Wegner first made his claim but didn't have the evidence to back it. He didn't even have a mechanisms to explain how it might have occured. The fact that we now accept continental drift as the best understanding of what happens is a testament to the power of science.
I should have explained the generality of it enough to satisfy your example about the ulcer example. Minority views sometimes become the majority view but more often than not they do not. Because we can show a number of examples when this happened, some people think the contrarian should always be considered the genius and more valuable than the concensus view. Again the contrarian view or minority view is more often than not wrong. Just as a few years ago some scientists came out with a journal article saying that something can travel faster than light. They were contrarians big time. As per usual in science - extraordinary claims require extraordinary evidence. And as would have been expected they had made mistakes in their experiments and mathematical calculations. Majority view is the current most correct view until proven otherwise with volumous or very clear evidence to the contrary.