Ellora Kailash Temple Built by Aliens

Featured post

10 Pictures facts you must know this Sunday

download (17)--all continents1. Each continent on the earth starts and end with same letter
2.The word Queue is the only word pronounced same as first letterimages--Q
3.The earth we live in is the only planet in solar system not named after a God because human live here .images--earth in solar system
4.Elephant is the only mammal on earth which can not jump.019 - Copy
5.More people are killed by bees than by snakes.

download (11)--Honey bee
6.More number of people are allergic to cow milk than other food.
download (3)--cow milk
7.Pure honey is only food which never spoils.Proved from Egypt Pharaoh (3)--pure honey
8.Most of the dust particles on your bed are from dead skin.images--dust of skin
9.The longest flight in time recorded for a chicken is 13 (30)
10.It is impossible to sneeze with open eye .download (17)--sneeze with eye

Featured post

The 5-step guide to fixing almost any PC problem


Troubleshooting is curious skill. It’s part detective work, part methodical experimentation and part inspired guesswork, and part Zen Buddhism.

That’s a lot of parts but you need them all to be able to sift through a list of symptoms, identify the fault, work out an appropriate remedy and not go barking mad in the process.

Knowing how computers work is also handy, but it isn’t enough by itself and it’s much less important than you may think, now that all human knowledge is just a Google search away. Knowing the answers is all very well but the real art is asking the right questions. See what I mean about the Zen?

So I’m not going to give you a fish. I’m not even going to teach you how to fish. I’m going to build you a stinking trawler. Theoretically this ought to put me out of a job but in practice, the well of human stupidity seems to replenish itself far faster than I can pump it out, so there’s no need to worry on my behalf.

Before we begin, let us consider the tools of the trade, which are: 1. Another computer 2. A screwdriver 3. A credit card. That’s it.

The screwdriver I use has a nice flowery handle and a reversible, socket barrel with two double-ended bits so I can swap between Phillips and flat-head in two sizes each, but really, just the smaller of the two Phillips heads would do for 90 per cent of the time.

The other computer should be working and connected to the internet. Ideally, it ought to be a desktop PC of roughly the same vintage as the computer you wish to fix, but even a laptop is better than nothing.

Among the many things you will not need include: a set of watchmaker’s screwdrivers, needle-nose pliers, soldering iron, can of compressed air and anti-static wrist strap. I have owned and recommended all of these things in the past, but I’ve never actually used any of them except to impress people when I go round to their houses to fix something.

You’ll still see computer magazines listing this ‘essential troubleshooting toolkit’, but it’s honestly just there to fill up a page. You are now equipped to attack the five different types of computer problem, which we shall deal with in turn.


This may sound like it could cover every computer problem but it’s actually quite specific. IUTWANID (pronounced yoot-wannid) means that your computer was working perfectly satisfactorily in the recent past and then something changed that either prevent the PC working at all or disables a significant component completely.

At its most extreme, this covers virtually every PC that won’t boot. At one time they did boot and now they don’t – that’s IUTWANID. Less severe examples include the sound suddenly disappearing from games or not being able to connect to the wireless network anymore.

To fix IUTWANID, you need to identify the thing that has changed. If you’ve installed software, try uninstalling it. Unplug any new hardware, use System Restore to roll back the registry. Don’t overreact and reformat – that’s effectively rolling back too far. You’ll need to undo changes in strictly reverse chronological order.

Sometimes – often even – it will seem that nothing has, in fact, changed recently on your system. This is a common delusion and must be resisted (or beaten out of you). Remember, it used to work. The temptation of course, is to assume that some bit in your computer has just broken, spontaneously and for no reason. This does happen but it’s very, very very rare.

A lot of the reason why computer troubleshooting is so frustrating for most people is because they leap too quickly to a ‘something must be broken’ diagnosis and spend ages swapping stuff around inside their system to no effect. So make sure you have undone every change to your PC first – every software install, every driver update, every patch and every new cable.

If all of that draws a complete and utter blank, you can start cannibalising your other PC for components to begin ruling out broken stuff. But the snag is that almost everything you swap will require its own drivers and installing these is itself a change to the system. This is another reason for using this as a last resort.


Every time something doesn’t work on your system and instead you get a window that pops up and tries to blame you, we call this an error message. The standard operating procedure in this kind of situation is to type the error message into Google (on the spare PC, if necessary) and see what results come up.

The good thing about error messages is that you can guarantee that at least one other person has already figured out the solution. The bad thing is that lots of the solutions are idiotic. Yahoo Answers and are frequented by mouth breathers and you should ignore whatever they advise.

Forums attached to games sites aren’t generally much better. What you really want is a hardware or software manufacturer’s forum; a serious computer site like Ars Technica or Tom’s Hardware or Wikipedia (or, if you’re truly desperate, you could always try asking the knowledgeable folk at or the TechRadar forums).

If you can’t find anything from a top-drawer resource like that, try refining your search. You’ll need to try a different part of the error message as your search string, leaving out those hexadecimal numbers, or putting the numbers back in. If that doesn’t work try putting different parts of the message in quotes.

If you get it right, you’ll find a decent hit in the first three pages of Google results. If it takes more than that to get any solid results, you’re doing it wrong. Read two or three different forum threads on the topic if you can and do whatever they say fixed the problem for them.

The Blue Screen of Death (BSOD) is the limiting case for error messages and if you find yourself facing one, your best resource is going to be Microsoft itself.

First stop should be to take the specific error code for a spin on the Knowledge Base and follow the instructions. Because a BSOD is pretty catastrophic event, you can also treat this as a kind of IUTWANID instead, if you like.

This isn’t usually very productive, though, because it ignores the specific information in the error code, but if the Knowledge Base page is all together far too vague to be of any help at all, and you know you’ve changed something recently, this might be the quicker route.


“Rubbish”, in this context nearly always means slower, but this category can also be applied to worsening sound quality, sticking keyboards or increasingly noisy fans. It’s different from IUTWANID, because it refers to a progressive, chronic deterioration.

If you had 80fps yesterday and only a mere 20 today, that’s IUTWANID, but if you used to be able to play games at acceptable frames rates and nowadays it seems much jerkier, then we call it IMRTIUTB. The key word in that last sentence is “seems”.

Often slowdown is more about your increasing expectations than decreasing performance. When your PC is new, you’re excited and predisposed to think well of it, so the thrashing sound of the hard disk feels like the revving of a powerful engine. That same PC two years later is old and grubby and subconsciously you would love to have an excuse to replace it; now the hard disk seems to wheeze asthmatically. Same noise, different spin.

There are two standard responses to IMRTIUTB; upgrade or reformat and reinstall. Both are wrong. Money spent on an upgrade delays the purchase of your next PC and offers much less benefit per pound than a new system. Upgrading is also like trying to balance a wobbly table; each new component you add creates a bottleneck or an incompatibility somewhere else and what started as just an extra 1GB of RAM quickly becomes a new motherboard, CPU, graphics card and PSU.

Reformatting and reinstalling seems like it will get you back to the halcyonicity of a new PC, but you have to remember that all the patches, updates and new drivers downloaded since then will still need to be reinstalled and they were responsible for much of the original slowdown.

Instead, IMRTIUTB is best addressed by uninstalling things. Any game, demo, shareware utility or Internet Explorer toolbar add-on that you do not depend on for your life needs to be removed. If you have more than eight icons in your System Tray, get rid of half of them.

All software thinks it’s so important that it must run constantly in the background. This is incorrect. Whatever it’s doing can wait. Possibly for eternity. Any other kind of IMRTIUTB is probably dirt. Take the lid off, blow away the dust, run your keyboard through the dishwasher and stop eating pizza while you play Crysis.


We live in a deterministic universe. The movement of stars, the radioactive decay of atoms and everything in between is controlled by immutable physical laws. We just don’t know what all of them are yet.

If your PC crashes, halts, fails or stymies you, every time something else happens, then it’s either IUTWANID or IGAEM. If it only sometimes happens, what you have is RATH. From a wide enough perspective, of course, random faults are just deterministic ones whose cause you haven’t managed to identify yet. But some causes are better at appearing random than other causes.

Overheating is the classic example of this. Your computer mostly works when you turn it on, but somewhere between a few minutes and an hour after that, it reboots or locks up or the graphics goes very peculiar or the sound goes screwy. Overheating is quite easy to diagnose – rebooting immediately, doesn’t help but shutting down and leaving it for a while does.


However, other ‘random’ influences are harder to isolate: radio frequency interference from nearby electrical equipment; heavy network traffic; dry solder joints on circuit boards, broken wires in cables; power surges in the domestic supply.

Be methodical, write down a hypothesis, devise a test, record the result and repeat the experiment to confi rm your conclusion. Or, just take it as a sign that it’s time for your next PC.


We all want to do the ‘New Thing’. The New Thing is exciting and wonderful. All the magazines are talking about the New Thing. Every website has banner ads reminding you that the New Thing will help you meet girls, earn more money and prevent cancer.

The New Thing is good because it’s new. But the New Thing doesn’t work on your old PC. It doesn’t fit in the slot, has the wrong number of pins, requires too much RAM and gives you unacceptable frame rates. The New Thing also doesn’t work in your new PC. It’s really quite buggy still, requires constant driver updates, doesn’t let you run in high resolution and causes all your USB ports to stop responding.

Faced with this, most of you will either blame the old PC or the New Thing. A few may even blame everything on the new PC. But in fact, the blame lies with you. It’s your fault for wanting the New Thing. It’s your fault for thinking you could just install it and skip merrily along. It’s entirely your fault for believing that the New Thing would be reliable and trouble-free.

This is not the way of the New Thing. Wherever possible, PCs should only have new software or hardware added in the first year of their lives. Doing this gives you a reasonable chance that your hardware configuration was considered when the developers were developing. After that year, you can continue to use your PC, of course; just don’t add anything new to it.

If the computer isn’t connected to the internet, you could, theoretically, stay in this holding pattern forever, but a networked PC will need to download Windows updates at the very least and your orbit will gradually decay. This, coupled with the fact that you will inevitably occasionally ignore this rule, which will lead to IMRTIUTB over time and when your PC is somewhere between 18 months and three-years-old, you will buy a new one.

This, if you absolutely must, is the time to invest in the New Thing. Stipulate to the supplier in writing that you are buying the PC for this purpose, thereby making compatibility a condition of sale. If possible, get the supplier to install the New Thing for you. Then it’s his fault (and therefore problem) if you get ICDNT.

The best approach of all, is not to do the New Thing at all. Wait a while; six months or a year. This will turn the New Thing into the Established Thing. The Established Thing is cheaper and has had the rough edges knocked off it. And the forums are already full of helpful advice should you run into IGAEM.

14 Super-Useful Yet Relatively Unknown Websites

Useful websites are a dime a dozen – however truly useful functionality for everyday people to make digital (or real) life easier are often hidden. Here are some websites that can help navigate that road and what they do. Or just have some fun!

  1. – Includes incredibly useful tools including a date to date calculator that calculates the number of days, hours, minutes, seconds, even percentage of the year between two dates. Also includes working out all days, or only workdays. Optional time field and zone conversions available.
  2. – A website requiring absolutely no photo editing skills that enables you to create full size, web-ready image affects that are also ready to print out onto any size paper and format – even large posters!
  3. 10 Minute Mail – A website that enables a temporary email address that will self-destruct after 10 minutes. Amazingly useful for access to websites requiring registration to subscription-based services without wanting all the spam that comes with it.
  4. Fake Name Generator – A website that can instantly create a fake identity – complete with phone number, address, birthday, nationality, country and even finances – you name it!
  5. Account Killer – A website devoted to helping you kill a social media profile dead, not just disabling it. Good for those looking to start their social media over.
  6. SkyScanner – A flight-scanning website that lists, in order of price and date, all the carriers offering a flight between destinations. Super simple use.
  7. Reverse Dictionary – Enter in a concept or related words, even a whole sentence, and this tool will attempt to give you a list of words that it thinks you’re after.
  8. Strip Creator – A website that enables you to make a comic strip quickly and easily – great for social media these days!
  9. Join Me – A web-based application that allows two people to screen-share. Great for problem solving issues from abroad or helping a friend out. Also great to simply use as a conversing tool over collaboration of content.
  10. A Good Movie To Watch – Great little tool to help suggest a movie to watch. Even lets you input the subscription service or services you’re subscribed to so it can ensure the movie suggested is available to you. Great for indecisives!
  11. My Fonts – A website that uses ‘WhatTheFont!’ to identify the font you’re looking for from an image, website or screenshot. Awesome if you’re trying to replicate a certain look!
  12. Adobe Color – Great for anything from Instagram wannabe’s through to professional web designers. Adobe Color lets you pick a colour tone (or range of colours) and suggests a themed colour palette to suit that style.
  13. Print Friendly – While we still live in a paper-using world, this is a super useful tool to transform any website into a printer-friendly version of it. Even complex crazy layouts are nicely converted.
  14. Google Trends – Last but certainly not least – Google Trend is an amazing tool that allows you to see, in real time, everything that is trending across the internet. It catalogues all google searches, globally, and delivers it in a super-useful layout so you can stay atop of whatever is trending. It allows you to choose what country you want the trends for as well as filter it by type. It’s like a hashtag, but for the whole web. Probably my favourite of this

26 Most Wanted Photoshop

Actions For Designer, Photographer & Digital Artist

If you’re a graphic designer, photographer or digital artist, Photoshop action can help you automate your hard work, such as applying a series of repetitive changes to a group of images. Here is list of 26 most wanted Photoshop actions that will give your images or designs stunning effects.

Animated Glitch

 Animated Glitch - Photoshop Action

This Action will generate a video sequence of animated glitch effects from your photos, logo or artwork. The effects are packed in clips and are easy to edit in the Timeline of Photoshop, in few clicks you’ll be able to make many variations and then export the file as a normal image, animated gif or video!


Retro Painting Machine

 Retro Painting Machine - Vintage Effect Action

This action gives you a quick & easy possibility to apply an high quality retro / vintage / old style painting effect to your photos & images.


Double Exposure

 Double Exposure Photoshop Action

Double exposure is a photographic technique that combines two images into one. With this action, you can create better double exposure in half the time.


Neon Maker Action Set

 Neon Maker Action Set

This set of Photoshop actions will help you in creating high quality and hi-resolution realistic neon effects. Action works well with any kind of objects such as vector shapes any text and art layers.



 Sketch Photoshop Action

Simplify your life and do not spend hours of time trying to create effects like this manually, get it done in minutes with only a few clicks. Get this action and it will turn your photo in to a sketch.


Square Potraits

 Square Potraits Photoshop Action

This action was made carefully using a multi language method and it has been tested on English and French version of Photoshop.


Retro Vintage Text Effects Vol. 2

 Retro Vintage Text Effects Vol. 2

You can use it on simple text, shapes and vector logo. You just need to replace them into the smart object of your favourite style included. Create a great poster or flyer, a facebook cover, a magazine title or a website banner and give them the vintage touch.


Clean Sketch

 Clean Sketch - Photoshop Action

This action is designed to transform your photo’s into sketch look.


Materials Type Effects

 Materials Type Effects

Materials Type Effects is a Photoshop Action Set for styling Type or Custom Lettering.


Neon Styles

 Neon Styles Bundle

These Neon signs are very fun and easy to customize. Simply edit with your own text, or if you wish to create your own template I have included the ASL files.


Typo Portrait

 Typo Portrait Pro Photoshop Action

This is a Photoshop Action to convert your simple image to Typographic master piece. Results are very professional with minimal user interactions.


25 HDR Photo FX V.1

 25 HDR Photo FX V.1 - Photoshop Action

Easily create true HDR or DRI photos from just one image or multiple exposures with these HDR Pro Photoshop Actions.


Pro 3D Text Mockups V1

 Pro 3D Text Mockups V1

3D text PSD and action files to help you create high quality, elegant 3D text easily and quickly.


Vintage Retro Text Effects

 Vintage Retro Text Effects Col 8

Create distinctive vintage typography with this retro text effect action.


Leather Badge Generator

 Leather Badge Generator - Photoshop Actions

Generate realistic leather elements from your text, logo, shape or design in few clicks.


Instagram Filter

 Instagram Filter - Photoshop Action

This action is designed to transform your photo’s into instagram filter look.


Christmas Felt Maker

 Christmas Felt Maker

This set of Photoshop actions will help you in creating high quality, good performance and realistic results related on stitched felt effect. Action works well with any kind of objects such as vector shapes text and art layers.


Smoke Action

 Smoke Action

Photoshop actions that will allow you to create realistic “smoke photo effects”.



 RainStorm Photoshop Action

Photoshop actions that will make your images look as if they are seen through the wet window while it rains. Make it rain in your photos without getting your camera wet!


Creative Retouch

 Creative Retouch

Make your photos look perfect with Creative Retouch photoshop action!


Minimal Town Maker

 Minimal Town Maker

This set of Photoshop actions will help you to easily create a map from any shape. The final result is a suface consisting of block squares, no matter what were the edges of the original shape. Also, the final result takes the shape contour. Once you’ve generated the surface, you can add any vector shape items that are included in the kit.


Low Poly Generator

 Low Poly Generator Photoshop Actions

Photoshop actions with styles intact that will allow you to create geometric low poly effects out of any image. The result contains easy to edit layers with layers styles intact so that you can customize the effect.


Cartoon Text Effects

 Cartoon Text Effects

Very easy to use. Replace the text in seconds via smart object layers. Works with text, vector shapes or logos.


Electrum PS Action

 Electrum PS Action

Incredible Photoshop action Pro with effect of electric lighting. Easy to change color, contrast and gradient of lighting.


Cinematic 3D Movie Mockups

 Cinematic 3D Movie Mockups

Realistic 3D effect easy for you to make with this 3D Mockup. Easy to change the colors of the Backgrounds.


Vibrant Watercolor Effect

 Vibrant Watercolor Effect - Photoshop Action

Photoshop plug-in that converts your photo in realistic watercolor painting. Just run the action and watch your drawing come to life!


Prev: 8 Useful Websites For Pairing Google Fonts
Next: 43 Cool HTML Coming Soon Templates

The First Poem Written for Computers


For you somewhat cybernetically challenged, it goes something like this (using the proper cyber-names):

		Waka waka bang splat tick tick hash,
		Caret quote back-tick dollar dollar dash,
		Bang splat equal at dollar under-score,
		Percent splat waka waka tilde number four,
		Ampersand bracket bracket dot dot slash,
		Vertical-bar curly-bracket comma comma CRASH


Welcome to, featuring completely free books from a variety of different authors, collected here for you to read online or offline. The books may have been published before, but not in this form, which I hope you find enjoyable to read and print. Feedback is welcome – enjoy the reading.

“The site was something I would never have thought to look for but as I’ve seen it now it has been a wee surprise. I work offshore on a pipe-laying vessel and spend six weeks at a time at sea, now I have a little library of works to read that I print off and use in my off shift.
The other guys on-board are using it too and it’s thanks to yourself we’ve got some interesting reading.”

How to get rid of Diabetes

*Logic of the Liver for treatment of human body*

Dr.Biswaroop Roy Choudhury`s Diets Program

Some Important Website for your need

Hey Webber

A lot websites with different functions are present on internet but some of them are unknown to us.
I’m writing this article to provide you the websites that are most used by the people.
In this 101 websites are given these will help you a lot .

  • – record movies of your desktop and send them straight to YouTube.
  • – capture screenshots of web pages on mobile and desktops.
  •– shorten long URLs and convert URLs into OR codes.
  •– find the original URL that’s hiding behind a short URL.
  • qClock– find the local time of a city using a Goo* Map.
  • -copy special characters that aren’t on your keyboard.
  • – a better search engine for twitter.
  • – create flowcharts, network diagrams, sitemaps, etc.
  • iconfindercom – the best place to find icons of all sizes.
  • – download templates, clipart and images for your Office documents.
  • – the easiest way to setup email reminders.
  • – scan any suspicious file or email attachment for viruses.
  • wolfra malpha .com – gets answers directly without searching.
  • printwhatyouli – print web pages without the clutter.
  • – reformats news articles and blog content as a newspaper.
  • – a search engine for RSS feeds.
  • – a simple online timer for your daily needs.
  • – if a site is down due to heavy traffic, try accessing it through coral CON.
  • – pick random numbers, flip coins, and more.
  • – lets you can quickly edit PDFs in the browser itself.
  • PDFs and Presentations directly in the browser.
  • – simultaneously upload videos to WuTube and other video sites.
  • -online voice recognition in the browser itself.
  • scrim -share you email address online without worrying about seam.
  • – now get read receipts for your email.
  • – visualize and compare the size of any product.
  • – quickly determine the font name from an image.
  • – a good collection of open source fonts.
  • – find data hidden in your photographs -see more BitIF tools.
  • livestream .com – broadcast events live over the web, including your desktop screen.
  • -helps you search domains across all TLDs.
  • – design from scratch or re -model your home in 3d.
  • – share you screen with anyone over the web.
  • – recognize text from scanned PDFs – see other OCR toots.
  •– Track flight status at airports worldwide.
  • – for sharing really big files online.
  • – the site lets you download free Kindle books.
  • polish – check your writing for spelling or grammatical errors.
  • highlight the important parts of a web page for sharing.
  • – work on the same document with multiple people.
  • – planning an event? find a date that works for all.
  • – a less confusing view of the world time zones.
  • – the perfect tool for measuring your site performance online.
  • – print music sheets, write your own music online (review).
  • moire – chat with your buddies on Skype, Facebook, Google Talk, etc. from one place.
  • – translate web pages, PDFs and Office documents.
  • – create paintings and sketches with a wide variety of brushes.
  • – discover new sites that are similar to what you like already.
  • – quick summarize long pieces of text with tag clouds.
  • – create mind -maps, brainstorm ideas in the browser.
  • – get color ideas, also extract colors from photographs.
  • -share your photos in an album instantly.
  • – when your friends are too lazy to use Google on their owl.
  • – when you need to find the name of a song.
  • bing.conVimages– automatically find perfectly -sized wallpapers for mobiles.
  • – send an online fax for free – see more fax services.
  • feed – get RSS feeds as an email newsletter.
  • – quickly send a file to someone, they can even preview it before downloading.
  • -transfer files of any size without uploading to a third -party server.
  • – setup a private chat room in micro -seconds.
  • – create text notes that will self-destruct after being read.
  • boxoh .com –track the status of any shipment on Google Maps – attemative.
  • – when you need to raise funds online for an event or a cause.
  • – find if your favorite website is offline or not?
  • – find the other websites of a person with reverse Analytics lookup.
  • – find the web host of any website.
  • – found something on Google but can’t remember it now?
  • – an online audio editor that lets record, and remix audio clips online.
  • – create a temporary web page that self-destruct.
  • – find definitions of slangs and informal words.
  • – consult this site before choosing a seat for your next flight.
  • – download stock images absolutely free.
  • zoom it – view very high -resolution images in your browser without scrolling.
  • -create custom Google Maps easily.
  • – quickly setup email reminders for important events.
  • – Picnik is offline but PicMonkey is an even better image editor.
  • – you can ask or answer personal questions here.
  • – an excellent layer -based online image editor.
  • -find if that email offer you received is real or just another scam.
  • – master touch-typing with these practice sessions.
  • – send video emits to anyone using your web cam.
  • – create timelines with audio, video and images.
  • – make a movie out of your images, audio and video dips.
  • – check the trust level of any website.
  • – a beautiful to-do app that looks like your paper dairy.
  • – you’ll need this when your bookmarked web pages are deleted.
  • – quickly capture effective notes during meetings.
  • youtube.corn/leanback-Watch YouTube channels in TV mode.
  • – quickly create a video playlist of your favorite artist.
  • – Send tweets longer than 140 characters.
  • – create a free aid simple website using your Dropbox account.
  • built – find the technology stack of any website.
  • – research a website from the SW perspective.
  • – broadcast live audio over the web.
  • – bookmark online videos and watch them later (review).
  • – add OR codes to your documents and presentations (review).
  • – the easiest way to write short text notes in the browser.
  • – send rich -text mails to anyone, anonymously.
  • – hire people to do little things for $5.
  • – easily manage your online files on Dropbox, Google Does, etc.
  • – create a connection between all your online accounts


Intra Atomic & Molecular Forces

Fundamental Forces


Fundamental force concepts

Coupling constants

HyperPhysics***** Quantum Physics R Nave
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The Strong Force

A force which can hold a nucleus together against the enormous forces of repulsion of the protons is strong indeed. However, it is not an inverse square force like the electromagnetic force and it has a very short rangeYukawamodeled the strong force as an exchange force in which the exchange particles are pions and other heavier particles. The range of a particle exchange force is limited by the uncertainty principle. It is the strongest of the four fundamental forces

Since the protons and neutrons which make up the nucleus are themselves considered to be made up of quarks, and the quarks are considered to be held together by the color force, the strong force between nucleons may be considered to be a residual color force. In the standard model, therefore, the basic exchange particle is the gluon which mediates the forces between quarks. Since the individual gluons and quarks are contained within the proton or neutron, the masses attributed to them cannot be used in the range relationship to predict the range of the force. When something is viewed as emerging from a proton or neutron, then it must be at least a quark-antiquark pair, so it is then plausible that the pion as the lightest meson should serve as a predictor of the maximum range of the strong force between nucleons.

The sketch is an attempt to show one of many forms the gluon interaction between nucleons could take, this one involving up-antiup pair production and annihilation and producing a πbridging the nucleons.

Feynman diagrams and the strong force

Fundamental force concepts

HyperPhysics***** Quantum Physics R Nave
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The Electromagnetic Force

One of the four fundamental forces, the electromagnetic force manifests itself through the forces between charges (Coulomb’s Law) and the magnetic force, both of which are summarized in the Lorentz force law. Fundamentally, both magnetic and electric forces are manifestations of an exchange force involving the exchange of photons. The quantum approach to the electromagnetic force is called quantum electrodynamics or QED. The electromagnetic force is a force of infinite range which obeys the inverse square law, and is of the same form as the gravity force.

The electromagnetic force holds atoms and molecules together. In fact, the forces of electric attraction and repulsion of electric charges are so dominant over the other three fundamental forces that they can be considered to be negligible as determiners of atomic and molecular structure. Even magnetic effects are usually apparent only at high resolutions, and as small corrections.


Fundamental force concepts

HyperPhysics***** Quantum Physics R Nave
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The Weak Force

One of the four fundamental forces, the weak interaction involves the exchange of the intermediate vector bosons, the W and the Z. Since the mass of these particles is on the order of 80 GeV, the uncertainty principle dictates a range of about 10-18 meters which is about 0.1% of the diameter of a proton.

The weak interaction changes one flavor of quark into another. It is crucial to the structure of the universe in that

1. The sun would not burn without it since the weak interaction causes the transmutation p -> n so that deuterium can form and deuterium fusion can take place.

2. It is necessary for the buildup of heavy nuclei.

The role of the weak force in the transmutation of quarksmakes it the interaction involved in many decays of nuclear particles which require a change of a quark from one flavor to another. It was in radioactive decay such as beta decay that the existence of the weak interaction was first revealed. The weak interaction is the only process in which a quark can change to another quark, or a lepton to another lepton – the so-called “flavor changes”.

The discovery of the W and Z particles in 1983 was hailed as a confirmation of the theories which connect the weak force to the electromagnetic force in electroweak unification.

The weak interaction acts between both quarks and leptons, whereas the strong force does not act between leptons. “Leptons have no color, so they do not participate in the strong interactions; neutrinos have no charge, so they experience no electromagnetic forces; but all of them join in the weak interactions.”(Griffiths)

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Fundamental force concepts

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Feynman Diagrams for Weak Force

A free neutron will decay by emitting a W, which produces an electron and an antineutrino.

When a neutrino interacts with a neutron, a W can be exchanged, transforming the neutron into a proton and producing an electron.

This interaction is the same as the one at left since a W+ going right to left is equivalent to a Wgoing left to right.

A neutron or proton can interact with a neutrino or antineutrino by the exchange of a Z0.

One of the four fundamental forces, the weak interaction involves the exchange of the intermediate vector bosons, the W and the Z. Since the mass of these particles is on the order of 80 GeV, the uncertainty principle dictates a range of about 10-18 meters which is about .1% of the diameter of a proton. The weak interaction changes one flavor of quark into another. For example, in the neutron decay depicted by the Feynman diagram at left above, one down quark is changed to an up quark, transforming the neutron into a proton.

The primitive vertices in the Feynman diagrams for the weak interaction are of two types, charged and neutral. For leptons they take the following form

The electron is used as an example in these diagrams, but any lepton can be substituted on the incoming side. The exit side (top) will be the same for the neutral vertex, but determined by the charge of the W in the charged vertex. Besides conserving charge, the vertex must conserve lepton number, so the process with the electron can produce an electron neutrino but not a muon neutrino.

The neutral interaction is simpler to conceive, but rarely observed because it competes with the much stronger electromagnetic interaction and is masked by it.
With the charged vertices, one can postulate an interaction like
mne -> e, nm and draw a Feynman diagram for it. This interaction is not likely to be oberved because of the incredible difficulty of observing the scattering of neutrinos, but it suggests other interactions which may be obtained by rotating or twisting the diagram.
With a twist of the Feynman diagram above, one can arrive at the interaction responsible for the decay of the muon, so the structures obtained from the primitive vertices can be used to build up a family of interactions. The transformation between the two Feynman diagrams can also be seen as an example of crossing symmetry.

Twisted Feynman diagrams and crossing symmetry

The charged vertices in the weak interaction with quarks take the form

So it is seen that the quark changes its flavor when interacting via the W or W+. As drawn, this interaction cannot be observed because it implies the isolation of an up quark. Because of quark confinement, isolated quarks are not observed. But rotating the Feynman diagram gives an alternative interaction, shown below for both electron and muon products.

This suggests the weak interaction mechanism for the decay of the pion, which is observed to happen by the muon pathway.

The weak interaction in the electron form at left above is responsible for the decay of the neutron and for b

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