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Philosophical discussions and debate

 "...the further great minds advance, the more ordinary people they leave behind." - Kenneth W. Krause.
a web site that bridges the divide

 
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HOW WE KNOW...

This page answers questions about how the scientific method can deduce amazing things about our universe. How do we know that there is a black hole at the center of our galaxy? The short answer is that we can measure the properties of a black hole by watching how it affects things around it. How do we know there was a big bang? Just as a glowing ember in a pile of ash is a sign of fire in the recent past, the big bang has left behind evidence that is equally compelling.

We will cover topics that span black holes to the ghostly action of quantum mechanics and how we use the scientific method to understand the mysteries of things unseen.

A Black Hole at the Center of the Milky Way

Our journey will start from Newton's law of gravity and how it was tested by earthbound mortals. I did the experiments in grad school, but don't trust me, you can do them too!

Then we investigate how this simple and elegant theory predicts the mass of the earth, the moon's motion about the earth and the earth's motion about the sun. Finally, by peering at the center of the Milky Way using telescopes that cut through the intervening dust, we can see the stars that orbit the central black hole. From the observed orbits, we can determine the mass and approximate size of the dark object. The evidence all points to a huge black hole. More

The Big Bang

Stay tuned....

 

 
 
 

The Scientific Method

  1. Make observations
  2. Develop testable hypotheses based on observations
  3. Design experiments to test hypotheses
  4. Develop laws based on experimental data
  5. Develop theories that predict and unify the observed laws
  6. Continually test the theories
  7. Go back to the drawing board when experiments and hypotheses/laws/ theories don't agree
  8. If a theory withstands the test of time, it is accepted by scientists provided that it continues to be robust

 

Interesting Quotes

“The first principle is that you must not fool yourself - and you are the easiest person to fool.” -- Richard Feynman
"Religion is regarded by the common people as true, by the wise as false, and by rulers as useful ."- Seneca (4BCE- 65 CE)
“How do we know that our holy books are free from error? Because the books themselves say so. Epistemological black holes of this sort are fast draining the light from our world..."- Sam Harris
"A tyrant must put on the appearance of uncommon devotion to religion. Subjects are less apprehensive of an evil treatment from a ruler they consider god fearing and pious. On the other hand they less easily move against him believing that he has the gods on his side" - Aristotle (384-322 BCE)
“We were convinced that the people needs and requires this faith. We have therefore undertaken the fight against the atheistic movement, and that not merely with a few theoretical declarations: we have stamped it out.” - Adolf Hitler, in a speech in Berlin on 24 Oct. 1933
"Therefore be on your guard against the Jews, knowing that wherever they have their synagogues, nothing is found but a den of devils in which sheer self-glory, conceit, lies, blasphemy, and defaming of God " - Martin Luther (On the Jews and Their Lies)
"...it is undesirable to believe in a proposition when there is no ground whatsoever for supposing it true.” - Bertrand Russell
“Without religion you have good people doing good things, and evil people doing evil things. But for good people to do evil things, it takes religion.” - Steven Weinberg
 

How do we know that...

  1. there's a massive black hole at the center of our galaxy?

  2. the universe formed in a big bang?

  3. evolution really happened and its going on today?