Holographic Universe: Fermilab to Probe Smallest Space-Time Scales

Conceptual design of the Fermilab holometer (Fermilab)

Conceptual design of the Fermilab holometer (Fermilab)

During the hunt for the predicted ripples in space-time — known as gravitational waves — physicists stumbled across a rather puzzling phenomenon. Last year, I reported about the findings of scientists using the GEO600 experiment in Germany. Although the hi-tech piece of kit hadn’t turned up evidence for the gravitational waves it was seeking, it did turn up a lot of noise.

Before we can understand what this “noise” is, we need to understand how equipment designed to look for the space-time ripples caused by collisions between black holes and supernova explosions.

Gravitational wave detectors are incredibly sensitive to the tiniest change in distance. For example, the GEO600 experiment can detect a fluctuation of an atomic radius over a distance from the Earth to the Sun. This is achieved by firing a laser down a 600 meter long tube where it is split, reflected and directed into an interferometer. The interferometer can detect the tiny phase shifts in the two beams of light predicted to occur should a gravitational wave pass through our local volume of space. This wave is theorized to slightly change the distance between physical objects. Should GEO600 detect a phase change, it could be indicative of a slight change in distance, thus the passage of a gravitational wave.

While looking out for a gravitational wave signal, scientists at GEO600 noticed something bizarre. There was inexplicable static in the results they were gathering. After canceling out all artificial sources of the noise, they called in the help of Fermilab’s Craig Hogan to see if his expertise of the quantum world help shed light on this anomalous noise. His response was as baffling as it was mind-blowing. “It looks like GEO600 is being buffeted by the microscopic quantum convulsions of space-time,” Hogan said.

Come again?

The signal being detected by GEO600 isn’t a noise source that’s been overlooked, Hogan believes GEO600 is seeing quantum fluctuations in the fabric of space-time itself. This is where things start to get a little freaky.

According to Einstein’s view on the universe, space-time should be smooth and continuous. However, this view may need to be modified as space-time may be composed of quantum “points” if Hogan’s theory is correct. At its finest scale, we should be able to probe down the “Planck length” which measures 10-35 meters. But the GEO600 experiment detected noise at scales of less than 10-15 meters.

As it turns out, Hogan thinks that noise at these scales are caused by a holographic projection from the horizon of our universe. A good analogy is to think about how an image becomes more and more blurry or pixelated the more you zoom in on it. The projection starts off at Planck scale lengths at the Universe’s event horizon, but its projection becomes blurry in our local space-time. This hypothesis comes out of black hole research where the information that falls into a black hole is “encoded” in the black hole’s event horizon. For the holographic universe to hold true, information must be encoded in the outermost reaches of the Universe and it is projected into our 3 dimensional world.

But how can this hypothesis be tested? We need to boost the resolution of a gravitational wave detector-type of kit. Enter the “Holometer.”

Currently under construction in Fermilab, the Holometer (meaning holographic interferometer) will delve deep into this quantum realm at smaller scales than the GEO600 experiment. If Hogan’s idea is correct, the Holometer should detect this quantum noise in the fabric of space-time, throwing our whole perception of the Universe into a spin.

For more on this intriguing experiment, read the Symmety Magazine article “Hogan’s holometer: Testing the hypothesis of a holographic universe.”

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Compex Magnetic Eruption Witnessed by Solar Observatories

Solar Dynamics Observatory view of the solar disk shortly after eruption (NASA).

This morning, at 08:55 UT, NASA’s Solar Dynamics Observatory (SDO) detected a C3-class flare erupt inside a sunspot cluster. 100,000 kilometers away, deep within the solar atmosphere (the corona), an extended magnetic field filled with cool plasma forming a dark ribbon across the face of the sun (a feature known as a “filament”) erupted at the exact same time.

It seems very likely that both events were connected after a powerful shock wave produced by the flare destabilized the filament, causing the eruption.

A second solar observatory, the Solar and Heliospheric Observatory (SOHO), then spotted a huge coronal mass ejection (CME) blast into space, straight in the direction of Earth. Solar physicists have calculated that this magnetic bubble filled with energetic particles should hit Earth on August 3, so look out for some intense aurorae, a solar storm is on its way…

For more on this impressive solar eruption, read my Discovery News article, “Incoming! The Sun Unleashes CME at Earth

Black Holes, Aurorae and the Event Horizon Telescope

My impression as to how a black hole 'aurora' might look like near an event horizon (Ian O'Neill/Discovery News)

Usually, aurorae happen when the solar wind blasts the Earth’s atmosphere. However, black holes may also have a shot at producing their very own northern lights. What’s more, we might even be able to observe this light display in the future.

Accretion Disks and Magnetic Fields

Simulating a rapidly spinning black hole, two researchers from Japan modeled an accretion disk spinning with it.

Inside this disk would be superheated plasma and as it rotates it might act like a dynamo, charged particles generating a magnetic field looping through the disk. But this magnetic field wont stay confined to the disk for long. Due to inertial effects, the magnetic field would be dragged into the event horizon, causing the magnetic fieldlines to ‘attach’ themselves to the black hole.

Assuming the accretion disk continues to generate a continuous magnetic field, a global black hole ‘magnetosphere’ would result.

A diagram of the black hole's magnetosphere (Takahashi and Takahashi, 2010)

A Plasma Hosepipe

As you’ve probably seen in the striking imagery coming from the high-definition movies being produced by the Solar Dynamics Observatory, magnetic fieldlines close to the solar surface can fill with solar plasma, creating bright coronal loops. This hot plasma fills the loops, feeding around the magnetic field like a hosepipe filling with water.

The same principal would apply to the black hole’s magnetosphere: the looped magnetic field feeding from the accretion disk to the event horizon filling with plasma as it is sucked out of the disk (by the black hole’s dominating gravitational field).

As you’d expect, the plasma will fall into the black hole at relativistic speeds, converted into pure energy, blasting with intense radiation. However, the Japanese researchers discovered something else that may happen just before the plasma is destroyed by the black hole: it will generate a shock.

As predicted by the model, this shock will form when the plasma exceeds the local Alfven speed. For want of a better analogy, this is like a supersonic jet creating a sonic boom. But in the plasma environment, as the plasma flow hits the shock front, it will rapidly decelerate, dumping energy before continuing to rain down on the event horizon. This energy dump will be converted into heat and radiation.

This fascinating study even goes so far as predicting the configuration of the black hole magnetosphere, indicating that the radiation generated by the shock would form two halos sitting above the north and south ‘poles’ of the black hole. From a distance, these halos would look like aurorae.

Very Large Baseline Interferometry

So there you have it. From a spinning black hole’s accretion disk to shocked plasma, a black hole can have an aurora. The black hole aurora, however, would be generated by shocked plasma, not plasma hitting atmospheric gases (as is the case on Earth).

This all sounds like a fun theoretical idea, but it may also have a practical application in the not-so-distant future.

Last year, I wrote “The Event Horizon Telescope: Are We Close to Imaging a Black Hole?” which investigated the efforts under way in the field of very large baseline interferometry (or “VLBI”) to directly observe the supermassive black hole (Sagittarius A*) living in the center of our galaxy.

In a paper written by Vincent Fish and Sheperd Doeleman at the MIT Haystack Observatory, results from a simulation of several radio telescopes as part of an international VLBI campaign were detailed. The upshot was that the more radio antennae involved in such a campaign, the better the resolution of the observations of the ‘shadow’ of the black hole’s event horizon.

If the black hole’s event horizon could be observed by a VLBI campaign, could its glowing aurorae also be spotted? Possibly.

For more, check out my Discovery News article: “Can a Black Hole Have an ‘Aurora’?” and my Astroengine.com article: “The Event Horizon Telescope: Are We Close to Imaging a Black Hole?

Gecksteroids! Asteroids and Geckos May Share Common Force

The asteroid Itokawa (as imaged by the Japanese Hayabusa probe) and a gecko tattoo. Bear with me, it'll make sense soon (JAXA)

The asteroid Itokawa (as imaged by the Japanese Hayabusa probe) and a gecko tattoo. Bear with me, it'll make sense soon (JAXA)

What do asteroids and geckos have in common? Not a lot, as you’d expect, but they may share a common force.

This rather strange notion comes from research being done by a team of University of Colorado scientists who have been studying the odd nature of the asteroid Itokawa. When the Japanese Hayabusa mission visited the space rock in 2005 (Hayabusa’s sample return capsule is set to return to Earth on June 13th by the way), it noticed the asteroid was composed of smaller bits of rubble, rather than one solid chunk. Although this isn’t a surprise in itself — indeed, many asteroids are believed to be floating “rubble piles” — the rate of spin of the asteroid posed a problem.

Itokawa spins rather fast and if only the force of gravity was keeping the lumps of rock together, they would have been flung out into space long ago. In short, the asteroid shouldn’t exist.

Although plenty of theories have been bandied around, one idea seems to stick.

More commonly found as a force that holds molecules together, the van der Waals force may bind the individual components of the asteroid together, acting against the centripetal force caused by its spin.

But where do the geckos come in?

Geckos are highly skilled in the “climbing up walls” department, and it’s the van der Waals force that makes this happen. Should the body of a gecko be tilted in such a way against a perfectly smooth, “impossible” to climb surface, the gravity acting on the little creature will trigger the force into action. Therefore geckos have evolved to exploit the practical application of van der Waals.

This has some rather interesting ramifications for asteroid evolution too. During early stages of asteroid formation, the larger fragments of rock are flung off; the centripetal force exceeds that of gravity. In the latter stages of development, only the smallest rocks remain behind, their mass small enough to allow van der Waals forces to overcome the spin.

So, there you have it, asteroids do have something in common with geckos. It seems only right to call these space rubble piles “Gecksteroids.”

Thanks to my Discovery News colleague Jennifer Ouellette for drawing the comparison between asteroids and geckos!

Source: Discovery News, arXiv.org

Hubble Conquers Mystic Mountain

Where is that mystical land? (NASA/ESA/HST).

Where is this mystical land? (NASA/ESA/HST).

Sometimes, words are not enough to describe views of the universe when captured through the lens of the Hubble Space Telescope. This is one of those moments.

Kicking off its 20th anniversary (yes, that super-sized telescope has been in space that long — I would say that I remember it being launched, but I don’t, because I was nine, playing with my Star Wars toys), Hubble has published some astonishing images of deep inside the Carina Nebula, some 7,500 light-years from Earth. And, quite frankly, I’m floored.

BIG PIC: Have a look deep inside the Carina Nebula with some of my Discovery News coverage of the event.

The pillar of gas and dust looks like a gnarled tree branch, dotted with sparkling lights. The Hubble press release even describes the structure as a “Mystic Mountain,” and it’s not hard to see why. In this age of computer generated everything, this release of images show that the cosmos contains things that defy our tiny imaginations.

We are looking at a star-forming region, deep inside the nebula, where stars are being born inside the bulbous towers of gas and dust, but on the outside, young stars are battering the tower with intense stellar winds and powerful radiation. The pillar is being eroded away. However, this exterior pressure is seeding the birth of new stars inside the nebulous material.

The mindblowing clarity of this Hubble observation even brings out the fine detail in the jets of ionized gas as it is blasted from the point of the tallest finger of material. This is being generated by a young star, gorging itself on gas, forming a superheated accretion disk, blasting the energized gas out from the stellar nursery.

As Hubble’s 20th anniversary celebrations continue, I think we can expect a lot more where this came from. So brace yourself, this gem of a space telescope may be getting old, but it still has a shedload of cosmos to show us.

Now, lets stand back and get a better view of the incredible floating ‘Mystic Mountain’…

The Carina stellar nursary from afar (NASA/ESA/HST)

The Carina stellar nursary from afar (NASA/ESA/HST)

Then Spitzer Imaged Baby Stars in the Orion Nebula…

The Orion Nebula's star-forming region (NASA)

The Orion Nebula's star-forming region (NASA).

Firstly, apologies that it’s been over a month since last posting to Astroengine.com. Call it slacking off, call it a sabbatical, either way, it’s not good. I’ve actually prepared several half-finished articles, but I just never got around to completing them. However, I have been on writing overdrive over at Discovery News, so if I go quiet over here, you know where to find me.

Speaking of Discovery News, I’ve just posted an incredible image of the heart of the Orion Nebula as seen by the Spitzer Space Telescope, so I can’t think of a better way to kick-start Astroengine with an image filled with awesomeness.

Although Spitzer has entered a new phase of operations since it depleted the liquid helium coolant used to maintain its instrumentation, that doesn’t mean its stopped producing some awe-inspiring imagery. In a new vista released on Thursday, a bustling star formation region in Orion is detailed, showing some 1,500 young stars the observatory watched for 40 days. This is an unprecedented study, allowing rapid variations in these baby stars to be tracked by Spitzer.

Young stars are generally highly variable in their brightness, a characteristic that is of huge interest to astrophysicists. If we can understand the mechanisms causing this variation, we can gain an insight to stellar evolution, possibly even understanding the history of our own Solar System.

As Spitzer observes in infrared wavelengths, it’s very sensitive to clouds of dust being heated by these young stars. Therefore, the proto-planetary disks surrounding these million year old stars glow brightly. Not only does this give an indication to the conditions surrounding the star, it also provides astronomers with an idea to how these disks of dust clump together, slowly evolving into exoplanets. And now Spitzer has data sets spanning weeks, dynamic changes in the emissions from the stars and their evolving planetary systems can be studied.

But science aside, the Spitzer imagery is a thing of beauty, reminding us how complex our cosmos really is. Don’t believe me? Take a look for yourself (click the pic to dive right in):

The star forming region in Orion as studied by Spitzer, rotated 90 degrees (NASA/JPL/Caltech)

The star forming region in Orion as studied by Spitzer, rotated 90 degrees (NASA/JPL/Caltech)

How are Black Holes Used in the Movies?

Source: Graph Jam

I mean, is the spaghettification of John Cusack using awesome 2012 doomsday graphics too much to ask? Instead of an improbable alien spacecraft appearing over the White House, why not use a black hole, producing so much tidal shear that it rips the building apart brick-by brick? Oh, and then have all the matter being sucked into the black hole accelerate to relativistic velocities, creating an X-ray belching accretion disk, lighting up the solar system with our planet’s regurgitated mass-energy? Movie audiences will have a total doomgasm over that!

Or we could just use it as a nifty time travel device.

*I just saw this on Graph Jam, had a giggle. More sci-fi black holes please!

Warning, Over-Hyped Title Alert: But It’s A Frackin’ SUPERNOVA!

I’m not kidding, last week was a huge mess of a supernova doomsday circus. It was like whispering “there’s a bomb under your chair” to the person next to you in a crowded theater and then watching the resulting flood of people slam into the fire escape. It was internet chaos. And there was no stopping it.

I am of course talking about the first, great doomsday scare of 2010: T Pyxidis.

Luckily for me, the first headline I saw was in the UK’s Telegraph that read “Earth ‘to be wiped out’ by supernova explosion.” Uh oh, that title sounds rather definite. Immediately, the bullshit sensor in my brain was tripped so I stopped flicking through the embarrassing excuse for a UK newspaper and had a read.

According to the article, some star (that I can’t pronounce) was “set to self-destruct” (as a big hairy supernova), a little over 3,000 light years away. Global chaos will therefore ensue. The ozone layer will be stripped away… and the Earth will be “wiped out.” (I still can’t work out how the Earth will be “wiped out.”)

I’m only picking on the Telegraph.co.uk as my skepticism knives were already sharpened after a series of idiotic woo-fueled articles (here, here and here) the website has played host to in recent months, but they weren’t the only news outlet to go batshit crazy with the “WE’RE ALL GONNA DIE” angle.

But who was really to blame for this mess? After all, the media was just the messenger, they must have gotten their lead from somewhere. Ah yes, the scientists… what did those guys really say?

You can find out how I got to the bottom of the science behind the hype in my Discovery News article “Will Earth ‘Be Wiped Out’ by a Supernova?” but cutting to the chase, it turns out that the scientists may have been a little hasty in their attempt to make international headlines.

As my mate Phil Plait mentions in his excellent write up (about my write up) of the T Pyxidis debacle on Bad Astronomy, this isn’t just a simple case of media hype, a lot of the blame should lay with Edward Sion et al. from Villanova University in Philadelphia.

Sure, some of the numbers didn’t add up (mistakes happen), but issuing a press release with a huge wad of inaccurate doom wrapped inside is pretty irresponsible. Have a read for yourself:

An interesting, if a bit scary, speculative sidelight is that if a Type Ia supernova explosion occurs within [that distance] of Earth, then the gamma radiation emitted by the supernova would fry the Earth, dumping as much gamma radiation (~100,000 erg/square centimeter) into our planet [sic], which is equivalent to the gamma ray input of 1000 solar flares simultaneously. –Excerpt from the Villanova press release, “THE LONG OVERDUE RECURRENT NOVA T PYXIDIS: SOON TO BE A TYPE Ia SUPERNOVA?”

“…fry the Earth”? Come on, that’s not even an accurate scientific term about what would happen if we were hit by a surge of gamma-rays. What’s wrong with saying “…the Earth would be at the receiving end of a Death Ray”? If you’re going to do the job of the tabloid press, hyping up your own research before the tabloid press has even read the release, you may as well be accurate.

And speaking of accuracy, my colleague Ray Villard was at the AAS and confirmed that Sion’s numbers were out by a factor of 10. “A supernova would have to be 10 times closer [to Earth] to do the damage described,” Ray said.

Although I was tough on the Telegraph in my Discovery News article (let’s face it, with an inaccurate and inflammatory title like that, they had it coming), in this case I think the main issue lies with Sion and co.

Why over-hype your research to get attention, when the research was interesting enough without declaring doomsday? By me even writing about the subject again, I think I just answered my own question.

But on a plus point, at least everyone knows what T Pyxidis is now…

The LHC Black Hole Rap… Best Yet

Released in December 2009, Kate McAlpine (a.k.a. AlpineKat) put together the rather fun “Black Hole Rap” in an effort to trivialize the disinformation being peddled about the Large Hadron Collider (LHC). You might remember AlpineKat from the hugely popular (and deliciously geeky) “LHC Rap” that has generated over 5 million hits on the YouTube video. Here’s the newest music video filmed in the depths of the French-Swiss border:

Unfortunately, the crazy “LHC Doomsday Suit” that tried (and failed, miserably) to stop LHC operations is still fresh in people’s minds. However, physicists have stepped up to the plate to debunk the claims and the LHC is happily colliding protons to its heart’s content. I love it how science wins, despite the noise made by a few crazed doomsday wingnuts…

Detecting Gravitational Waves on the Cheap

Forget building gravitational wave detectors costing hundreds of millions of dollars (I’m looking at you, LIGO), make use of the most accurate cosmic timekeepers instead and save a bundle.

The North American Nanohertz Observatory for Gravitational Waves (NANOGrav) is a proposal that involves closely monitoring the regular flashes of spinning neutron stars (or pulsars) to detect very slight “shimmers” in their signal. Although the physics is crazy-complex, by tracking these shimmers over a suitably distributed number of pulsars could reveal the passage of gravitational waves.

However, there’s a problem with this plan; pulsars are notoriously tricky stellar objects, as my colleague Jennifer Ouellette points out:

The problem is that you need to closely monitor rapidly-spinning millisecond pulsars, which are (a) tough to find (only 150 have been found over nearly three decades since pulsars were first discovered), and (b) not very plentiful in the part of the night sky of interest to scientists (northern hemisphere). They tend to clump together in globular star clusters, which makes them useless for detecting gravitational waves.

However, according to results announced by the National Radio Astronomy Observatory (NRAO) at this week’s American Astronomical Society (AAS) meeting in Washington D.C., they’ve discovered 17 new pulsars with the help of NASA’s Fermi Gamma-Ray Space Telescope.

In addition to recent Fermi telescope pulsar discoveries, it would appear that the number of potential targets for NANOGrav are increasing, making a stronger case for the 10 year, $65 million project…

You have to wonder whether building the Laser Interferometer Gravitational-Wave Observatory (LIGO) was worth it (but you can’t be too careful, some terrorist organizations might want to use gravitational waves for evil, so it would be good if we detected them first).

Source: Discovery News