Imagine Magazine - Johns Hopkins - September/October 2011 - (Page 10)

PHYSICS IS... SHUTTErSTOCK Computing on the quantum scale In the world as we know it, objects can be in only one place at a time. But when you get down to the size of atoms and smaller, the laws of quantum mechanics take over. Now, objects like the electron in a hydrogen atom only have a certain likelihood of being in a particular place. Until you try to pinpoint the electron, it is in all its allowed places. Quantum mechanical particles have the funky ability not only to be in multiple places at once, but to be in more than one state at the same time. In computers, for instance, memory is stored in “bits” that can have one of two states: a zero or a one. But quantum bits, or qubits, can be both a zero and a one. This multitasking allows qubits to process more information. One day, this could mean much faster computers, but for now, it’s very difficult to get more than a few qubits working at the same time. Just last spring, researchers at the University of California, Santa Barbara unveiled a new machine containing four qubits, and they believe they could make a 10-qubit system later this year. Researchers say that a quantum computer with qubits numbering in the hundreds could be more powerful than all the computers in the world put together—and it could happen in the next few decades. Querying the cosmos When physicists look into space, they are also looking back in time. The nearest star is four light-years away, which means that any changes we see in the light reaching Earth happened at that star four years ago. Now astrophysicists can see much further than that. Last January, researchers announced the discovery of the oldest known galaxy, an incredible 13.2 billion light-years away. The universe itself is estimated at 13.7 billion years old, so that light that the Hubble telescope detected comes from the universe’s very infancy. In addition to working out the universe’s timeline, physicists are also striving to understand what it’s made of. It turns out that familiar objects like stars, planets, black holes, and gas account for a small fraction of the mass in the universe. The rest is dark matter, which forms an invisible framework under the galaxies we see. To find out what it is, physicists are hunting it with detectors in space and deep in mines—and they are also trying to create it in laboratories. Nano-managing technology As nanotechnology creeps out of the lab and into shops—in the forms of wrinkle-resistant clothing, sunscreens, and ultra-strong bicycle parts, to name a few— the fields of research developing it continue to grow. Whether scientists make modified materials or very tiny machines, the unifying theme of this area is its scale: about the width of a strand of hair, divided by a thousand. Nanomaterials can have properties much different than their full-size versions. For instance, carbon nanotubes are chemically the same as the stuff in pencil lead, but these one-atom-thick tubes conduct electricity better than copper and are stronger than steel. Some nanotechnology is as simple as mixing tiny particles of one material with another to change its properties, such as adding carbon nanotubes to concrete for extra strength. But scientists are also trying to engineer robots that act on a molecular or atomic level, and some researchers are already working on developing tiny machines that propel themselves through our blood vessels to take drugs straight to where they are needed. 10 imagine Sept/Oct 2011

Table of Contents for the Digital Edition of Imagine Magazine - Johns Hopkins - September/October 2011

Imagine Magazine - Johns Hopkins - September/October 2011
Contents
Big Picture
In My Own Words
Physics Is…
Making the Team
Nuclear by Nature
Physics: The Next Generation
Telescopic Views
Exploring the Mysterious Lives of Stars
Around the Universe in Three Weeks
Selected Opportunities & Resources
Book Buddies
Meeting the (Economics) Challenge
Off the Shelf
Word Wise
Exploring Career Options
One Step Ahead
Planning Ahead for College
Students Review
Creative Minds Imagine
Mark Your Calendar
Knossos Games

Imagine Magazine - Johns Hopkins - September/October 2011