1. image: download

    mothernaturenetwork:

Black holes cannot actually exist, according to mathematical proofThe scientific world is left reeling after a researcher offers breakthrough mathematical proof.

“According to her calculations, when a star collapses under its own gravity, it produces the Hawking radiation that scientists have observed. But, she argues, as the star gives off this radiation it also sheds mass. So much mass is shed, in fact, that the star loses density, and the formation of a black hole is prevented. Stars do not meet their death by collapsing into black holes, according to the proof. Rather, they swell one last time and then explode.”  
I recommend this other article (a little less sensationalist), written by an astrophycisist, about the Laura Mersini-Houghton paper : 
"This is interesting theoretical work, and it raises questions about the formation of stellar-mass black holes. But it doesn’t prove that stellar-mass black holes don’t exist, nor does it say anything about intermediate mass or supermassive black holes, which would form by processes other than stellar collapse. And of course the work depends upon Hawking’s take on firewalls to be correct, which hasn’t been proven. To say that this work proves black holes don’t exist is disingenuous at best" .

    mothernaturenetwork:

    Black holes cannot actually exist, according to mathematical proof
    The scientific world is left reeling after a researcher offers breakthrough mathematical proof.

    According to her calculations, when a star collapses under its own gravity, it produces the Hawking radiation that scientists have observed. But, she argues, as the star gives off this radiation it also sheds mass. So much mass is shed, in fact, that the star loses density, and the formation of a black hole is prevented. Stars do not meet their death by collapsing into black holes, according to the proof. Rather, they swell one last time and then explode.”  

    I recommend this other article (a little less sensationalist), written by an astrophycisist, about the Laura Mersini-Houghton paper : 

    "This is interesting theoretical work, and it raises questions about the formation of stellar-mass black holes. But it doesn’t prove that stellar-mass black holes don’t exist, nor does it say anything about intermediate mass or supermassive black holes, which would form by processes other than stellar collapse. And of course the work depends upon Hawking’s take on firewalls to be correct, which hasn’t been proven. To say that this work proves black holes don’t exist is disingenuous at best" .

     
  2. 11:36 9th Aug 2014

    notes: 2257

    reblogged from: einbear

    tags: physics

    curiosamathematica:

The double pendulum is chaotic: the behaviour of the system is extremely sensitive even to small perturbations. Notice for instance how the two pendulums in the animation start at almost the same position, but their motion drastically drifts apart soon.
Mathematica code by fouriestseries.

    curiosamathematica:

    The double pendulum is chaotic: the behaviour of the system is extremely sensitive even to small perturbations. Notice for instance how the two pendulums in the animation start at almost the same position, but their motion drastically drifts apart soon.

    Mathematica code by fouriestseries.

     
  3. 09:41 12th Jun 2014

    notes: 519

    reblogged from: clearscience

    tags: physics

    In a first for laser-driven fusion, scientists at a US lab say they have reached a key milestone called fuel gain: they are producing more energy than the fuel absorbed to start the reaction.
    — 

    Laser-sparked fusion power passes key milestone  |  New Scientist (February 2014)

    Okay, okay, okay, okay, guys. Scientists at the National Ignition Facility have taken the first itty bitty baby steps towards fusion and I’m having trouble containing my excitement.

    First of all, they’re using 192 laser beams, which are pointed at a gold chamber that converts the lasers into X-ray pulses, which then squeeze a small fuel pellet and make it implode and undergo fusion. That anyone ever figured out even how to do this is completely nutso.

    Secondly, the lead researcher is named Omar Hurricane. I have never in my life heard a better name. He sounds like a comic book character. Please someone write a comic starring Omar Hurricane and his band of laser-wielding scientists.

    And then there’s what it actually means. So far, they’ve been able to get 15 kilojoules of energy out of a fuel pellet that was blasted with 10 kilojoules. But, as The Guardian points out, much more energy is delivered by the lasers (and lost in the conversion to X-rays): “The lasers unleash nearly two megajoules of energy on their target, the equivalent, roughly, of two standard sticks of dynamite.” 

    Even so, this is a hugely significant tiny step forward toward recreating the clean energy production that happens in the heart of stars.

    (via chels)

    Due to a peculiarity of nuclear physics, you can release energy either by 1) breaking apart heavy atoms, or 2) forcing together light atoms. Breaking apart is called fission and forcing together is called fusion. We already know how to generate energy by man-made fission, but generating energy by man-made fusion remains an aspiration. (Of course, we know how to build bombs both ways. Nuclear and thermonuclear bombs respectively.)

    Essentially, solar power is fusion, though. Because the sun is a fusion reactor, and its light lands on our planet and makes everything happen. 

    (via clearscience)

     
  4. 12:42 3rd May 2014

    notes: 110

    reblogged from: extracts

    tags: astronomyphysics

    image: download

    extracts:

The Theory of Inflation
     
  5. plays: 1,263

    The Universe is Weird, Hank Green 

    (Thanks to socalreaper for the suggestion)

     
  6. 09:23 7th Apr 2014

    notes: 5946

    reblogged from: sagansense

    tags: Star Trekphysics

    (Source: horrormenagerie)

     
  7. 13:15 30th Mar 2014

    notes: 1564

    reblogged from: naydoh

    tags: illustrationcatphysics

    image: download

     
  8. 10:00 28th Mar 2014

    notes: 376

    reblogged from: rhamphotheca

    tags: physicsBig Bang

    rhamphotheca:

    ENORMOUSLY IMPORTANT FINDING IN PHYSICS:

    First glimpse of big bang ripples from universe’s birth

    Important evidence found for Big Bang

    by Lisa Grossman

    Waves in the very fabric of the cosmos are allowing us to peer further back in time than anyone thought possible, showing us what was happening in the first slivers of a second after the big bang. If confirmed, the discovery of these primordial waves will have rippling effects throughout science. It backs up key predictions for how the universe began and operates, and offers a glimmer of hope for tying together two foundational theories of modern physics. It might even net the discoverers a Nobel prize.

    The waves in question are called gravitational waves and are produced when a massive object accelerates through the fabric of space-time, causing ripples. They appear in Einstein’s highly successful theory of general relativity, although they have never been directly detected.

    Today [March 17], scientists working with the BICEP2 collaboration at the south pole announced the first clear sign of gravitational waves, found in maps of the earliest light emitted after the big bang. The distinctive swirls made by the waves are more pronounced than the team expected, because models had suggested that gravitational waves from this early era would be incredibly weak and perhaps even undetectable…

    (read more: New Scientist)

    more stories:

    Science News/AAAS

    Popular Science

    New Scientist

     
  9. Nearly a century ago, Albert Einstein suggested that time should move faster the farther away you are from the surface of the Earth. Now scientists have tested this theory at the small distances we travel up and down every day. Using the world’s most precise clocks, they confirmed that our wristwatches tick at a slightly different speed when we ride an elevator, climb a flight of stairs, or even sit upright in bed.

    […]
    This optical atomic clock uses lasers tuned to the vibrations of a single atom of aluminum, which wobbles more than a quadrillion times per second (a quadrillion is a 1 followed by 15 zeros). It keeps time to within a second for 3.7 billion years.

    Searching for time dilation, Chou and his colleagues put the clock on a table and raised the table by a foot. After a long observation, they found that the time on the raised clock was slightly ahead of the time on a second clock kept below.

    "The difference at a foot of height over 100 years would be about 100 nanoseconds, said Chou. "That’s about a hundred billionths of a second."

    Time, then, does not flow at a constant rate in our daily lives.

    "These small differences would have been undetectable for the previous generation of atomic clocks," said Chou, who published the results in the journal Science.

    All other things being equal, living upstairs causes you to age slightly faster than living downstairs. And even with both feet planted firmly on the ground, parts of your body at different heights will age differently.

    foxnews, 2010

     
  10. 09:38 6th Mar 2014

    notes: 113

    reblogged from: foundfilm

    tags: videoanimationphysics

    Why Do I Study Physics?