It’s all relative. How many times have you heard that? Well, when you’re traveling close to the speed of light, everything really is relative; especially the passage of time. This week, Fraser and Pamela give you the skinny on Einstein’s Special Theory of Relativity. After listening to a few thought experiments, you too should be …
Einstein was right. Well, according to new observations of a double pulsar, he was at least 99.95% right. An international team of astronomers have been measuring the pulsar pair for three years, and have detected several effects that match Einstein’s theory of general relativity. It’s believed the two pulsars are losing energy through the radiation …
Cosmologists from Princeton are working on new tests that could help to explain the nature of “dark energy”, a mysterious force accelerating the expansion of the Universe. It could be an unknown form of energy, or it could be that Einstein’s General Theory of Relativity breaks down at very large scales. The researchers will track the rate at which galaxy clusters have grown in time. If this growth is consistent, it’ll mean that dark energy is at work; otherwise, it could mean problems with Einstein’s predictions.
An international team of astronomers have performed a robust survey of quasars to confirm a prediction from Albert Einstein about how gravity should magnify the light traveling from distant objects. The study showed how the light from 200,000 quasars is being tugged by the gravity of 13 million galaxies as it travels from the quasars to the Earth. The researchers used the Sloan Digital Sky Survey to uncover thousands of new quasars which could then fine-tune their observations.
All Quasar’s have black holes for hearts – but that doesn’t mean they are unfriendly. In fact, 9 billion light year distant QSO2237+0305 may like us so much that it wants to make sure we see it even though it is actually hidden by a much nearer spiral galaxy. What can we learn from QSO2237+0305? For one, the cross that bears Einstein’s name can tell us a lot about space-time curvature. For another, it can teach us invaluable lessons about how to see things otherwise hidden from view. If you have access to the scope and the skies, you too can see what the whole spectacle is all about.
String theorists have a problem. They have a set of theories which could explain how all the forces in the Universe are connected. Unfortunately, it depends on the existence of tiny vibrating strings which are so small they could never be seen directly. One strategy, proposed by physicists from Yale, would be to look at the afterglow from the Big Bang, which covers the entire sky. The small strings could project much larger shadows onto this radiation which would be light-years across, and detectable from Earth.
We do live. We age. We move. Time is how we refer to the transfer of ourselves from our beginning to end. Space is how we scale things through our primary sense of vision. Using the scientific method we can define iota that are so incredibly abstract as to be partly in our universe and partly somewhere else. We are also pretty sure that as we have a beginning and end so does the universe in which we live. Much of the basis from which we draw this understanding is directly attributable to Albert Einstein. In Michio Kaku’s book, Einstein’s Cosmos, How Albert Einstein’s Vision Transformed Our Understanding of Space and Time we are taken on a wonderful brief journey through Einstein’s life and the development of his theories that establish this basis.
Theorists are working madly to develop the new “Theory of Everything” that will tie together all the forces in the Universe into one unified explanation. Experimenters are also working to come up with ways to test these various theories, and narrow down the ones that actually predict what happens in Nature. One upcoming experiment called LATOR will test how the Sun’s gravity bends light emitted by mini-satellites – it will be so precise that many theories will be invalidated if it doesn’t find deviations from Einstein’s predictions.
Image credit: NASA/JPL The Cassini spacecraft has provided a group of Italian researchers with data that confirms Einstein’s general theory of relativity with 50 times more accuracy than before. They measured the frequency shift of radio waves traveling to and from the spacecraft as they went by the Sun. They measured how much the Sun’s …
A team of European astronomers accurately measured the orbit of a star around the supermassive black hole at the center of our Milky way, thus confirming predictions made by Einstein’s theory of General Relativity.