Time Travel and You: A Beginner’s Guide

Time travel is the concept of moving between different points in time in a manner analogous to moving between different points in space. Time travel could hypothetically involve moving backward in time to a moment earlier than the starting point, or forward to the future of that point without the need for the traveler to experience the intervening period (at least not at the normal rate). Any technological device – whether fictional, hypothetical or actual – that would be used to achieve time travel is commonly known as a time machine.

Time Travel Methods

In technical papers, physicists generally avoid the commonplace language of “moving” or “traveling” through time, and instead discuss the possibility of closed timelike curves, which are worldlines that form closed loops in spacetime, allowing objects to return to their own past. There are known to be solutions to the equations of general relativity that describe spacetimes which contain closed timelike curves (such as Gödel spacetime), but the physical plausibility of these solutions is uncertain.

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Writing More Efficient CSS

Cascading Style Sheets (CSS) is a style sheet language used for describing the presentation semantics (the look and formatting) of a document written in a markup language. Its most common application is to style web pages written in HTML and XHTML, but the language can also be applied to any kind of XML document, including plain XML, SVG and XUL.

CSS is designed primarily to enable the separation of document content from document presentation.

CSS is designed primarily to enable the separation of document content (written in HTML or a similar markup language) from document presentation, including elements such as the layout, colors, and fonts. This separation can improve content accessibility, provide more flexibility and control in the specification of presentation characteristics, enable multiple pages to share formatting, and reduce complexity and repetition in the structural content (such as by allowing for tableless web design).

.post code {
	background: #90979F;
	color: #fff;
	padding: 40px; 
}

CSS can also allow the same markup page to be presented in different styles for different rendering methods, such as on-screen, in print, by voice (when read out by a speech-based browser or screen reader) and on Braille-based, tactile devices. This separation can improve content accessibility, provide more flexibility and control in the specification of presentation characteristics, enable multiple pages to share formatting, and reduce complexity and repetition in the structural content (such as by allowing for tableless web design).

.post pre {
	background: #F9F9F9;
	font-family: "Courier 10 Pitch", Courier, monospace;
	font-size: 15px;
	line-height: 1.6;
	margin-bottom: 1.6em;
}

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