(PhysOrg.com) -- Engineers at Harvard have demonstrated a new kind of tunable color filter that uses optical nanoantennas to obtain precise control of color output.
Nanophysics
Feb 23, 2012
7
0
Search-and-rescue operations of boats carrying migrants across the central Mediterranean Sea did not appear to affect the rate of crossing attempts between 2011 and 2020, according to a modeling study published in Scientific ...
Social Sciences
Aug 3, 2023
0
65
In 1998 former tech consultant Hank Eskin launched a campaign to track dollar bills. Through the "Where's George?" initiative, dollars were stamped with messages about the currency tracking project, and people were instructed ...
General Physics
Mar 29, 2019
0
936
A new study has found ground-breaking evidence from an ice core in the Swiss-Italian Alps that proves the 7th century switch from gold to silver currencies in western Europe actually occurred a quarter of a century earlier ...
Archaeology
Nov 16, 2018
2
239
Is the web browser on your phone slower than usual? It could be mining bitcoin for criminals.
Security
Jun 29, 2018
0
358
Bitcoin may be the most famous cryptocurrency but, despite a dizzying rise, it's not the most lucrative one and far from alone in a universe that counts 1,400 rivals, and counting.
Internet
Jan 14, 2018
7
352
Never mind Bitcoin mania taking the doyen of virtual currencies into the stratosphere. The real online craze to get with right now is to breed virtual cats.
Internet
Dec 6, 2017
0
10
Bats often get the short end of the stick—when you look around in October, they're featured in Halloween decorations right up there with unsavory characters like monsters and ghosts. But these animals are key to their environments ...
Plants & Animals
Oct 16, 2017
2
113
Standing in a warehouse in a Moscow suburb, Dmitry Marinichev tries to speak over the deafening hum of hundreds of computers stacked on shelves hard at work mining for crypto money.
Internet
Aug 16, 2017
0
85
A dispute among developers of virtual currency Bitcoin gave birth Tuesday to a new version of the crypto coin after they failed to agree on software changes.
Internet
Aug 1, 2017
1
162
In economics, currency refers to a generally accepted medium of exchange. These are usually the coins and banknotes of a particular government, which comprise the physical aspects of a nation's money supply. The other part of a nation's money supply consists of bank deposits (sometimes called deposit money), ownership of which can be transferred by means of cheques, debit cards, or other forms of money transfer. Deposit money and currency are money in the sense that both are acceptable as a means of payment.
Money in the form of currency has predominated in human civilizations from about 10,000 BCE on. Usually (gold or silver) coins of intrinsic value (commodity money) have been the norm. However, nearly all contemporary money systems are based on fiat money – modern currency has value only by government order (fiat). Usually, the government declares the fiat currency (typically notes and coins issued by the central bank) to be legal tender, making it unlawful to not accept the fiat currency as a means of repayment for all debts, public and private.
This text uses material from Wikipedia, licensed under CC BY-SA
