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	Friday, Jan. 31, 2014

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Have a safe day!

Friday, Jan. 31

8:25 a.m. to 6:15 p.m.
ICFA Neutrino Panel Mini-Workshop - One West
Register in person.
Registration fee is $30.

2:30 p.m.
Theoretical Physics Seminar (NOTE DATE, LOCATION) - WH3NE
Speaker: Nima Arkani-Hamed, Institute for Advanced Study
Title: The Amplituhedron

3:30 p.m.
DIRECTOR'S COFFEE BREAK - 2nd Flr X-Over

4 p.m.
Joint Experimental-Theoretical Physics Seminar - One West
Speaker: Nima Arkani-Hamed, Institute for Advanced Study
Title: Toward the Next Big Circular Colliders

Sunday, Feb. 2

9 a.m.-5:30 p.m.
LBNE Collaboration Meeting
See website for agenda and details

Monday, Feb. 3

8 a.m-6:30 p.m.
LBNE Collaboration Meeting
See website for agenda and details

2:30 p.m.
Particle Astrophysics Seminar - Curia II
Speaker: Daniel Grin, University of Chicago
Title: Some New Isocurvature Directions

3:30 p.m.
DIRECTOR'S COFFEE BREAK - 2nd Flr X-Over

4 p.m.
All Experimenters' Meeting - Curia II

Click here for NALCAL,
a weekly calendar with links to additional information.

Ongoing and upcoming conferences at Fermilab

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Weather

Chance of snow
21°/17°

Extended forecast
Weather at Fermilab

Current Security Status

Secon Level 3

Current Flag Status

Flags at full staff

Wilson Hall Cafe

Friday, Jan. 31

- Breakfast: chorizo and egg burrito
- Breakfast: winner's waffle
- Super Bowl burger
- No-flag beef brisket
- MVP barbecue pork spareribs
- Touchdown turkey and cucumber salad wraps
- Big-game burrito
- Championship clam chowder
- Texas-style chili
- Assorted pizza by the slice

Wilson Hall Cafe menu

Chez Leon

Friday, Jan. 31
Dinner
Closed

Wednesday, Feb. 5
Lunch
- Chicken roulade with herbed cheese
- Spinach orzo
- Swedish apple pie

Chez Leon menu
Call x3524 to make your reservation.

Explain it in 60 seconds: quantum entanglement

Through "spooky action at a distance," the properties of two systems remain correlated even after they are separated. Image: Sandbox Studio

Quantum entanglement happens when two systems — such as two particles — interact. They develop correlations between their properties that are maintained even after they are separated by large distances in space. An observer measuring one system could perfectly predict the corresponding measurements of a second observer looking at the other system far, far away.

An example of an interaction that generates entanglement is the decay of a particle into two other particles: Due to conservation of momentum, the decay products must be entangled in a state where their momenta are correlated. If we measure the momentum of one particle, we know the momentum of the other.

Albert Einstein disparaged the possibility of this prediction, calling it "spooky action at a distance," but Erwin Schrödinger, and later John Bell, recognized it as an essential feature of quantum mechanics.

Although entanglement doesn't allow communication faster than the speed of light, it can be used to "teleport" a perfect quantum copy of an object (although one must destroy the original). Recent experiments have teleported quantum states well over 100 kilometers.

Entanglement isn't just a feature of esoteric experiments. Typical states of matter we encounter all the time are characterized by a large degree of entanglement. In fact, entanglement between objects and their environment is responsible for the emergence of the familiar classical world from counterintuitive quantum laws. The organization of entanglement in matter can also contain a great deal of interesting physical information.

More speculative recent work has suggested that entanglement might be the thread that stitches together different regions of spacetime in quantum gravity. Entanglement between different objects might even generate a wormhole in spacetime that connects them.

—James Sully, SLAC National Accelerator Laboratory

Photo of the Day

Winter sun

The sun over Fermilab breaks through the white in the sky onto the white on the ground on a recent morning. Photo: Tanya Levshina, SCD

In the News

R&D in the FY 2014 omnibus: the big picture

From AAAS News, Jan. 28, 2014

With the Consolidated Appropriations Act of 2014 officially signed into law, we can make some early assessments of how federal R&D funding will ultimately fare in FY 2014. Overall, the result is somewhat mixed, which is unsurprising given that the December budget deal only gave Congress so much room to work with. According to current AAAS estimates, federal R&D could end up at $136.2 billion in FY 2014, compared to $132.7 billion in FY 2013 and $142.5 billion in FY 2012.

On the surface, the FY 2014 figure appears to be a rather limited improvement from post-sequester spending. Indeed, the increase from FY 2013 only adds up to 2.6 percent, which will be almost entirely erased by inflation. But focusing only on the topline number is somewhat misleading, as there are divergent trends underneath those figures. If R&D in the spending omnibus is separated out by function, it becomes apparent that defense and nondefense R&D will move in two different directions (as will research versus technology development).

In the News

Synopsis: Looking for the invisible at colliders

From Physics, Jan. 29, 2014

We have no idea what dark matter is. Most attempts to unravel the mystery entail trying to directly detect primordial dark matter particles as they stream by Earth. But it is, in principle, possible to produce dark matter particles in colliders. Until now, bounds from direct detection have been stronger than such collider searches. Now, the ATLAS collaboration at the LHC reports in Physical Review Letters that it has used the absence of a certain type of such collider production to place the strongest constraints yet on some models of dark matter.

Frontier Science Result: CMS

How many quarks in a proton?

Although we usually say that a proton contains three quarks (up, up and down), there are many more quark-antiquark pairs at fine scales.

Matter is made of molecules, which are made of atoms, which are primarily made of protons and neutrons, which are made of quarks. In each case, however, "made of" takes a subtly different meaning. Protons are not made of quarks the way that a wall is made of bricks but rather like the way that a fire is made of flames. They are seething balls of spontaneously forming and annihilating quarks.

Yet this tempest has structure. For instance, quarks and antiquarks can only be created or destroyed in pairs, so when we say that a proton contains three quarks, it is because the total number of quarks minus the total number of antiquarks is always three (two more up quarks than anti-up and one more down quark than anti-down). Adding a few more quark-antiquark pairs doesn't change the difference.

The number of quarks plus the number of antiquarks depends on how closely you look. Just as a coastline seems to get longer as you zoom in (because the true coastline winds around every grain of sand on the beach), the number of quarks and antiquarks increases at finer scales. High energies are sensitive to small scales, so high-energy protons appear to be denser and are more likely to collide.

This affects the rate of production of every kind of particle made by the LHC. But because these high energies had never been explored before first collisions in 2010, no one knew for sure what the rates of particle production would be. In addition to searching for the Higgs boson and other new particles, physicists have been measuring familiar processes to get a clearer picture of how the proton's density scales with energy.

One very precise way to do that is to count the ratio of W+ bosons to W− bosons. A W+ boson is formed when an up quark and an anti-down quark combine, and a W− is formed from down and anti-up. Since protons contain more up quarks than down, W+ is somewhat more likely than W−. The exact ratio depends on the density of antiquarks, so CMS scientists carefully measured tens of millions of W+ and W- bosons with impressively small uncertainties (0.2 to 0.4 percent). These measurements are already helping to nail down the structure of the proton at the smallest scales.

—Jim Pivarski

The U.S. physicists pictured above made major contributions to this study of W charge asymmetry.

After years of effort, the above physicists are stepping down from senior leadership roles in CMS. As a group, they held managerial roles in computational resources, physics analyses and the detector upgrade. CMS thanks them for their effort and wishes them well in future endeavors.

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