His lucky guess was that the universe had an infinity of worlds like Earth. The show gives the impression that his guess was true, even if he lacked the evidence. But it is not. The overwhelming view of cosmologists today is that there are only a finite number of worlds in the universe.
He [Bruno] could not keep his soaring vision of the cosmos to himself, despite the fact that the penalty for doing so in his world was the most vicious form of cruel and unusual punishment. ... It wasn't long before Bruno fell into the clutches of the thought police.No. Bruno's heresy was that he was a Catholic monk who denied the divinity of Jesus Christ.
Our entire universe emerged from a point smaller than a single atom. Space itself exploded fire launching the expansion of the universe, and giving birth to all the matter and all the energy we know today.This is not helpful. I accept the Big Bang theory, but there is no real scientific evidence that the start was a point smaller than an atom. A naive extrapolation leads to that model, but the universe could have started with something the size of the Earth, for all anyone knows.
Anyway, we did not get an infinite number of worlds from a point smaller than an atom.
There is a lively debate between Scott Aaronson and Lubos Motl over whether P=NP. Aaronson eventually goes into a name-calling rant, and bans Motl from commenting on the blog for 3 years.
Aaronson has also banned me from his blog, because he was irritated about my skepticism of the possibility of quantum computers. Motl is his usually obnoxious and over-opinionated self, and he has called me names as well. Aaronson is like the Roman Inquisition, while Motl is like Bruno.
At the core of the dispute is the difference between math and science. P=NP is an open mathematical question, and until it is proved true or false, both outcomes must be considered possible. Aaronson's point is that the question should be considered settled under the lower standards of science, by analogy to the evidence for how green and yellow frogs might be separate species. Both Aaronson and Motl have weak arguments.
Aaronson is a typical academic knee-jerk liberal, and people like that usually despise political conservatives like Motl who can back up their opinions.
I once credited Aaronson with a plausible argument against P=NP, but I am doubtful about his frog argument:
He also argues that P != NP because verifying a proof ought to be much easier than finding an original proof. That is a reasonable argument. If it turns out that P = NP, then we would have to revise a lot of what we think about complexity, so we should be very skeptical of any such claim. Likewise we should be skeptical about quantum computing.While my intuition says that there can be no efficient algorithm to solve NP complete problems, there could be a very inefficient polynomial-time algorithm, thereby allowing P=NP.
Maybe I should have expressed my objections to quantum computing as a parable about frogs. Instead of the evidence and arguments, I could have told about a naked emperor who gave grants to find a purple frog, and everyone always reported great progress even tho no one ever found a purple frog.
Update: Jennifer Ouellette, wife of cosmologist Sean M. Carroll, reviews Cosmos in the LA Times:
And Tyson adds a 21st century twist by invoking the multiverse: the notion that our universe might be just a bubble among bubbles in a vast infinite sea of universes. That’s the kind of notion that used to fall firmly into crackpot territory – or make for bestselling science fiction novels -- but is now taken quite seriously by many cosmologists, even if it’s not (yet, if ever) a testable hypothesis. And it’s the perfect set-up to a charming animated sequence relating one of my favorite stories from the history of astronomy.Maybe taken serious by popularizers who promote fringe ideas like her husband. If an idea is never testable, then real scientists do not take is seriously as scientific.
Giordano Bruno was an Italian mystic who was among the first to adopt the Copernican cosmology at a time when doing so could prove hazardous to your health. In fact, he went one step further and suggested – based on a vision when he was 30, perhaps because he read the forbidden text of Lucretius, "On The Nature of Things" – that the sun and its planets were just one of millions of other solar systems in an infinite universe. It made sense to Bruno. God was infinite, he reasoned, so why shouldn’t the universe he created be infinite too?No, the dude was wrong. Where is the Inquisition when we need it?
The Catholic Church begged to differ and excommunicated him. So did the Protestant church. ...
But as Tyson points out, the dude was right. Sure, it was a lucky guess, and he wasn’t really a scientist, but “It gave others a target to aim at, if only to disprove it.”
This show could have told the story of any of 1000s of great scientists who made observations, formulated a hypothesis, did an experiment, and then correctly analyzed the data to come to a valid conclusion. Bruno did none of that. It is crazy for this first Cosmos episode to focus on idolizing someone who was so contrary to the scientific method.