His concept of Minkowski space is the earliest treatment of space and time as two aspects of a unified whole, which is the essence of special relativity. He hoped this new idea would clarify the theory of special relativity.
Minkowski spacetime is only accurate at describing constant velocity. It was Einstein, though, who discovered the curvature of space-time (gravity) in general relativity. In general relativity, Einstein generalized Minkowski space-time to include the effects of acceleration. Einstein discovered that the curvature in his 4-dimensional space-time representation was actually the cause of gravity.
The 1926 thirteenth edition of the "Encyclopedia Britannica" included an article by Einstein titled "space-time".
Edgar Allan Poe wrote an essay on cosmology titled "" (1848) which said that "space and duration are one". This is the first known instance of suggesting space and time to be different perceptions of one thing. Poe arrived at this conclusion after approximately 90 pages of reasoning but employed no mathematics.
In 1895, H.G. Wells in his novel, "The Time Machine", wrote, “There is no difference between Time and any of the three dimensions of Space except that our consciousness moves along it”. He added, “Scientific people…know very well that Time is only a kind of Space”.
In general relativity, spacetime is thought of as smooth and continuous. However, in the theory of quantum mechanics, spacetime is not always continuous.
Scottish Socialist Party
The Scottish Socialist Party (SSP; ; ) is a political party which was formed in 1998. It argues for socialism and Scottish independence.
Esztergom
Esztergom is a city in Hungary, 45 kilometers north of Budapest. 30 928 people live in Esztergom. It is the center of the Roman Catholic Church in Hungary, and the Constitutional court is in the city. There are a lot of rich museums in the city.
Esztergom is on the right side of the river Danube. There are big islands on the Danube. There are mountains to the east, that surround the city. The city is 100,35 km² big.
The city was founded in 972 by Géza of Hungary. It is one of the oldest cities in Hungary. Until 1249 it was the capital of the country. The archbishops built many schools, churches, palaces, and the kings of Hungary built castles. In 1242 the city was attacked and destroyed by mongols, but the castle on the hill was not. After the attack king Béla IV. moved to Buda, and gave the city to the archbishop. In 1543 the city was taken by the Turks, who built many spas. The Hungarians tried to take back the city many times, so it was destroyed again in the wars. The Turks left Esztergom in 1683. In 1822 Alexander Rudnay, the archbishop started building a big temple called a basilica. It is the biggest temple and the tallest building in the country, and the third biggest temple in Europe.
Public transport
Public transport (public transportation in the United States) is the transport of passengers. Passengers don't need their own cars or other vehicles. Most public transport lets many people travel at the same time.
Ships have carried passengers since prehistoric times. Early public transport by land became important in some places in western Europe in the early 19th century. Around 1826 horsedrawn omnibuses operated in Nantes, France. Omnibuses were carts with seats for passengers to sit. About the same time, railroads began carrying passengers between towns in England. Ferries (public boats) also became bigger and more numerous then.
The main vehicles for public transport are buses, trolleybuses, trams and trains. Trams were first used in the late 1860s and used to be pulled by horses. Now trams are electric and run on a line of cable. Buses drive on the road, like cars do. Trolleybuses are like buses, but they use electricity from two wires above the road. Trains run on a track and are very fast. Many places use trams and trains as a form of public transport.
Many people who do not have cars use buses, trolleybuses, trams to go places near their house, and they use trains to go places far away. Long distance transport is usually by airline or train or other public transport. Local transport is more often private.
When using public transport people may need a ticket or card to be able to get on. On trams they get a ticket that they put in a machine and it tells them when their ticket runs out. On buses and trolleybuses they buy their ticket from the driver and put it into a machine, and on trains they use a ticket to get onto their train. A timetable tells them when they come, since they can only go when and where the transport is going.
Public transport is also good for the environment. When many people use the same vehicle, fewer cars are on the road. Fewer cars make less pollution. Cost is low, because it is very cheap to catch public transport every day, which is why even people who own a car often use public transport.
Public transportation comes in many forms:
Some of these types are often not for use by the general public, e.g. elevators in offices and apartment buildings, buses for personnel or school children, etc.
Stations are an important aspect of any public transportation system. Specific types include:
In addition one can get on or off of a taxi at any road where stopping is allowed. Some fixed-route buses allow getting on and off at suitable unmarked locations along that route, typically called a hail-and-ride section.
Money is needed to build and operate a public transit system. The money comes from ticket revenue, government subsidies and advertisements. If ticket prices are too high, people will not use public transit. So, most systems charge passengers less than the full cost of building and operating the system. The percentage of total revenue that passengers pay is known as the farebox recovery ratio. Sometimes, a small amount of income comes from land development and rental income from stores and vendors, and parking fees. Some subway systems get money from telecommunication companies by leasing tunnels and rights-of-way to carry fiber optic communication lines.
For most–but not all–public transport systems, passengers must buy a ticket. Tickets may either be bought before the ride, at the time of the ride, or both. Tickets can be paper ticket, metal or plastic tokens, or an electronic card (smart card, contactless smart card). Sometimes, a ticket has to be validated (marking the time of the ticket's use). A paper ticket is stamped when it is validated. An electronic ticket is checked in.
Tickets may be valid for a single (or return) trip, or valid within a certain area for a period of time. The fare (price of the ticket) is based on the travel class, either based on the traveled distance, or on a zone pricing.
The tickets may have to be shown or checked automatically at the station platform or when going onto the system, or during the ride by a conductor. Operators may choose to control all passengers, allowing sale of the ticket at the time of ride. Alternatively, a proof-of-payment system allows passengers to enter the vehicles without showing the ticket. Riders may or may not be controlled by a ticket controller. If the rider does not show proof of payment, the operator may fine the rider.
Multi-use tickets allow a passenger to travel more than once. These include "return tickets" where the passenger pay for two trips at one time. It also includes period cards allowing travel within a certain area (for instance month cards), or during a given number of days that can be chosen within a longer period of time (for instance eight days within a month). Some transit systems sell tickets (passes) aimed at tourists that allow free or discounted entry at many tourist attractions, typically include zero-fare public transport within a city. Period tickets may be for a particular journey (in both directions), or for a whole network.