Science Says: Cost of Love Is Two Old Friends

In the economy of relationships, there's a price to falling in love. According to a new, as yet unpublished study from Oxford University, it's two friends. Brian Dunbar, an evolutionary anthropologist, conducted a survey that asked people about how their inner circle changed when they fell in love. His findings suggest that people have about five close confidantes at any one time. In order to make room for the new love interest, that circle shrinks.

"People who are in romantic relationships - instead of having the typical five [individuals] on average, they only have four in that circle," Dunbar told the BBC. "And bearing in mind that one of those is the new person that's come into your life, it means you've had to give up two others."

This may explain why some young males maintain the "bros over h-words" rule—to try to prevent their inner circle from being fragmented. It also explains why the sequel to Sex and The City didn't really work. (Well, that and the whole multiple costume changes in the middle of the desert thing...)

"What I suspect happens," says Dunbar, "is that your attention is so wholly focused on your romantic partner that you just don't get to see the other folks you have a lot to do with, and therefore some of those relationships just start to deteriorate and drop down into the layer below."

Dunbar is noted for previously having suggested that we can only really hold enough space in our brains to have relationships with 150 people, despite what our Facebook pages say. This has come to be known as Dunbar's number.

But evolutionary anthropology is not destiny, as they say in the classics. So even if we have to all roll over and two have rolled out to accommodate our bestie's new flame, nobody's circle is set in stone. After things have simmered down a bit, it's got to be possible to reconnect with good friends again, right? Unless of course, the new lover is unbearable, and there's the only one thing to do.

A BRIEF HISTORY OF The Light Bulb

Thomas A. Edison exhibits a replica of his first successful incandescent lamp, which gave 16 candlepower of illumination, in contrast to the ultimate in today's achievement, a 50,000 watt, 150,000 candlepower lamp.

Across Europe, it's just about lights out for the humble incandescent bulb. The European Union began phasing out incandescents on Aug. 31, banning stores from buying new stock.

It's all part of an effort to drive consumers toward a better bulb: Compact fluorescent lamps (CFL) that burn as much as 10 times longer while consuming less than a third of the electricity as incandescents. At as much as $10 each, CFL bulbs are more expensive, but experts say they pay for themselves in energy savings in just a few months. The European Union is even touting the switch as an economic stimulus, as experts estimate the swap to CFL will save customers €5 billion annually. Bucks-for-bulbs, anyone?

Though Thomas Edison is usually cited as the father of the light bulb, it's more accurate to give Edison credit as the creator of the first commercially viable light bulb. As early as 1820, inventors were honing in on the principles that would lead to the first electric illumination. An English inventor, Joseph Swan, took their early work and developed the basis of the modern electric light bulb in 1879 — a thin paper or metal filament surrounded by a glass-enclosed vacuum. When electricity runs through the filament, the light bulb glows. Edison refined the design, trying filaments made out of platinum and cotton before eventually settling on carbonized bamboo, capable of burning for more than 1200 hours. With Edison's design — and settlement of a lawsuit with Swan that resulted in the two inventors joining forces in 1883 — electric lighting became viable for the first time.

The development of the light bulb sparked the spread of electric power in America. Edison himself was behind the creation of the first commercial power plant in 1882, and New York City had electricity by 1892. By the late 1930's the Rural Electrification Administration, one of President Franklin D. Roosevelt's New Deal programs, had brought electric lighting into nearly every corner of the country. Development didn't stop on the bulb, either: Researchers have honed Edison and Swan's design further, refining the filament by using tungsten metal and filling the vacuum with gas, both of which increased the lifespan of a bulb even further. Still, even modern bulbs are inefficient — less than 6% of the energy used by a bulb goes into producing light. The rest is given off as heat.

CFL bulbs are designed to address this inefficiency. The technology for the bulbs was developed as early as the 1890s as lights but General Electric perfected the design during the U.S. energy crisis in the 1970s. CFL bulbs use electricity to excite mercury vapor, which produces ultraviolet light that is filtered through a coating on the bulb to become visible light. GE shelved the design, as the bulbs would have required new manufacturing plants, but the the specs leaked over the years. Though assembling a CFL bulb is still costly, the bulbs are environmentally friendly and save consumers money in the long run, forming the basis of the government-mandated switch.

But this mass changing-of-the-bulbs isn't one that's universally appreciated. CFL bulbs emit light in a different spectrum than their incandescent counterparts, producing a light that's "cooler" — tinged a light blue or green — than the yellowish hue of of an incandescent. Many complain the effect is less aesthetically pleasing. CFL bulbs also have their own environmental issues because of the danger of mercury exposure if bulbs break — making disposal tricky. Some also allege constant exposure to fluorescent light has caused health problems, though experts are largely skeptical of these claims.

These concerns, however, take a backseat to those over light bulbs' environmental impact — replacing a single incandescent bulb with a CFL in every U.S. household would be the environmental equivalent of taking 7.5 million cars off the road. The U.S. plans to follow Europe's lead, outlawing incandescents beginning in 2012. Still, at least one light will stay on: The Centennial Light in Livermore, Calif., has been shining continuously in the same firehouse since 1901, making it the longest-burning bulb on the planet.