This is the website:
http://science.discovery.com/tv/through-the-wormhole/
What is a Black Hole?
By William R. Harris, HowStuffWorks.com
Black Holes? Absurd!
Black holes are almost as difficult to imagine as they are to detect, but a few scientists have been up for the task over the centuries. Cambridge scholar John Michell wrote a paper in 1783 in which he hypothesized the existence of "dark stars" — stars so large and with so much gravity that light wouldn't escape their surfaces. Most astronomers of the day thought it was an absurd notion.
Then, in 1915, Einstein published his general theory of relativity, providing a framework that allowed for a reinterpretation of Michell's hypothesis. An Indian graduate student by the name of Subrahmanyan Chandrasekhar piggybacked on Einstein's theories to suggest that stars of a certain size — much larger than our sun — would experience a catastrophic collapse at the end of their lives, thereby transforming the bodies into cosmic vacuum cleaners whose powerful gravity could suck all light and matter into their black maws.
Tick, tock, tick -- wait. Time's not real?
When you're having fun, time flies. Waiting in a traffic jam, not so
much. Your birthday was last month, and your mortgage payment is due in a few
days. The fact that we perceive time is certainly no illusion. But is it really
there, or is it something we invented?
Early on in human history, we decided to start measuring the days and
weeks, and eventually hours, minutes and seconds. Time was useful in organizing
society, planting crops and getting ready for dates. Things worked extremely
well until scientists started muddling it all up.
Pesky Incongruities
In the 17th century, English scientist Isaac Newton was pretty sure time
existed as a universal constant. But in 1908, Hermann Minkowski, expanding on
one of Einstein's ideas on the relationship between space and time, suggested a
space-time continuum. This theory held that space and time were inextricably
mixed, with all events occurring along the same timeline. Einstein presented
his theory of general relativity not long after this and proposed that time is
but an illusion.
Around the same time (if you believe in time, that is), the field of
quantum mechanics grew out of an effort to explain the relationship between
matter and energy. This presented a little problem for scientists trying to
create a single, unified theory to account for the universe and its component
parts. Quantum mechanics requires the existence of time to work. General
relativity does not.
Three is the magic number, right?
For most of our history, we've rested easy in the notion that there were
three dimensions that have existed throughout time: length, width and height.
Ah, the good old days. In the early 20th century, Hermann Minkowski and Albert
Einstein connected our comfortable three dimensions with a fourth, time,
defining special relativity using a space-time continuum.
This kind of worked, but still didn't explain a troublesome new theory
of gravity called quantum mechanics that arose around the same time Minkowski
and Einstein were working on their theories. Quantum mechanics had its own
rules that contradicted the concepts behind the space-time continuum.
Scientists treated this incompatibility like the weather for decades,
discussing it but not really doing anything about it.
Who doesn't love (multi-dimensional) donuts?
While higher theoretical dimensions began with Descartes in the 1600s,
in the 1970s string theory expanded on this idea as physicists attempted to tie
everything together in one elegant explanation of the universe. Variations of
string theory require the existence of up to eleven dimensions and a slew of
universes, with our universe forming a three-dimensional membrane floating
around some higher-dimensional donut. According to this theory, each point in
space has six higher dimensions wrapped up in super-tiny geometries called
Calibi-Yau Manifolds.
One recent string theory suggests that the reason we only experience the
three spatial dimensions is that all universes with higher dimensions got into
some cosmic car accident and destroyed each other, leaving our measly
three-dimensional "brane" untouched
It probably wasn't long after ancient people developed a belief in the
afterlife that they began trying to contact those who had crossed over to the
other side.
Necromancy, the term for such communication with dead souls, comes from the
ancient Greek wordnekromanteia, but the practice dates back much further
than the Greeks. Egyptian and Chaldean magicians attempted to conjure up the
deceased and speak with them, and God specifically barred the ancient Hebrews
from engaging in the practice in Deuteronomy 18:10-11. In the epic poem
"The Odyssey," Homer describes his hero Odysseus casting spells
according to the instructions from the sorceress Circe, in an effort to speak
to the prophet Tiresias and gain assistance to return home. Roman neuromancers
believed that it was easiest to reach the dead in caverns and near volcanoes,
which they believed to be passageways to the underworld.
In Medieval and Renaissance Europe, occultists persisted in their
efforts to conjure up the dead and speak with them, even though in some
countries at various times, it was a crime punishable by death (that is, when
civil and/or ecclesiastic authorities weren't practicing it themselves). In
1664, for example, the famous English jurist Sir Matthew Hale convicted two
elderly women of "unlawful communication with infernal agents" and
sentenced them to hang. By the late 1700s, however, necromancy had resurfaced
and was being practiced again openly, thanks in part to the pioneering efforts
of George, First Baron Lyttelton, who published a manual called "Dialogues
with the Dead," which quoted his conversations with the classical Greek
statesman Pericles and the deceased Russian czar Peter the Great, among others.
In the 1800s, believers in necromancy even organized their own religion,
Spiritualism, and held gatherings called séances, during which
they attempted to contact the spirits of the deceased. The belief became so
popular that during the American Civil War, Mary Todd Lincoln held séances in
the White House in an effort to contact her dead son Willie. His father,
President Abraham Lincoln, dutifully attended those events. Typically, in
séances of the time, participants would gather around a table in a darkened
room, while the leader of the gathering, called the medium, would
cast an incantation and go into a trance that purportedly allowed the spirits
of the dead to enter his or her body and use it as an ethereal public-address
system. The medium would speak in the dead person's voice, or use a pen and
paper to convey messages, a practice called automatic writing.
Is Time Travel Possible?
Einstein's Theory of Relativity says that time travel is perfectly
possible — if you're going forward. Finding a way to travel backwards requires
breaking the speed of light, which so far seems impossible. But now,
strange-but-true phenomena such as quantum nonlocality, where particles
instantly teleport across vast distances, may give us a way to make the dream
of traveling back and forth through time a reality. Step into a time machine
and rewrite history, bring loved ones back to life, control our destinies. But
if we succeed, what are the consequences of such freedom? Will we get trapped
in a plethora of paradoxes and multiple universes that will destroy the fabric
of the universe?
Want to know more about time travel? Read on!
Could We Travel Back in Time, Thanks to Entanglement Physics?
By Susan Nasr, HowStuffWorks.com
By Susan Nasr, HowStuffWorks.com
Entangling Einstein
Einstein said that nothing travels faster than the speed of light, but
when physicists look at how entangled particles behave, they get stuck in a
mirage in which that tenet appears not to be true.
Physicists don't fully understand entanglement, beyond it being a
relationship between particles. If you want to know what entanglement looks
like, pull up a chair to an experiment that has produced it. Researchers at the
University of Nice-Sophia Antipolis and the University of Geneva shone a laser
made of photons, the basic units of light, into the crystal. When the laser's
photons hit irregularities in the crystal, single photons sometimes split into
two. These daughter photons were related to one another, and to their parent
photon, in how much energy they had.
You can think of the parent photon as being like a train, and the
crystal like many bumps. When the train hit the bumps, it broke into two chains
of cars with related directions and speeds. These daughter photons weren't just
related, but entangled. Particles are entangled if they're related in one
property but random in the rest.
ill start posting my stuff soon i promise
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