Area where direct light from a light source cannot reach due to obstruction by an object

A shadow is a dark area where light from a light source is blocked by an opaque object. It occupies all of the three-dimensional volume behind an object with light in front of it. The cross section of a shadow is a two-dimensional silhouette, or a reverse projection of the object blocking the light.

A point source of light casts only a simple shadow, called an "umbra". For a non-point or "extended" source of light, the shadow is divided into the umbra, penumbra, and antumbra. The wider the light source, the more blurred the shadow becomes. If two penumbras overlap, the shadows appear to attract and merge. This is known as the shadow blister effect.

The outlines of the shadow zones can be found by tracing the rays of light emitted by the outermost regions of the extended light source. The umbra region does not receive any direct light from any part of the light source and is the darkest. A viewer located in the umbra region cannot directly see any part of the light source.

By contrast, the penumbra is illuminated by some parts of the light source, giving it an intermediate level of light intensity. A viewer located in the penumbra region will see the light source, but it is partially blocked by the object casting the shadow.

If there is more than one light source, there will be several shadows, with the overlapping parts darker, and various combinations of brightnesses or even colors. The more diffuse the lighting is, the softer and more indistinct the shadow outlines become until they disappear. The lighting of an overcast sky produces few visible shadows.

The absence of diffusing atmospheric effects in the vacuum of outer space produces shadows that are stark and sharply delineated by high-contrast boundaries between light and dark.

For a person or object touching the surface where the shadow is projected (e.g. a person standing on the ground, or a pole in the ground) the shadows converge at the point of contact.

A shadow shows, apart from distortion, the same image as the silhouette when looking at the object from the sun-side, hence the mirror image of the silhouette seen from the other side.

The names umbra, penumbra and antumbra are often used for the shadows cast by astronomical objects, though they are sometimes used to describe levels of darkness, such as in sunspots. An astronomical object casts human-visible shadows when its apparent magnitude is equal or lower than -4.[2] The only astronomical objects able to project visible shadows onto Earth are the Sun, the Moon, and in the right conditions, Venus or Jupiter.[3] Night is caused by the hemisphere of a planet facing its orbital star blocking its sunlight.

A shadow cast by the Earth onto the Moon is a lunar eclipse. Conversely, a shadow cast by the Moon onto the Earth is a solar eclipse.[4]

The sun casts shadows that change dramatically through the day. The length of a shadow cast on the ground is proportional to the cotangent of the sun's elevation angleits angle relative to the horizon. Near sunrise and sunset, when = 0 and cot() = , shadows can be extremely long. If the sun passes directly overhead (only possible in locations between the Tropics of Cancer and Capricorn), then = 90, cot() = 0, and shadows are cast directly underneath objects.

Such variations have long aided travellers during their travels, especially in barren regions such as the Arabian Desert.[5]

The farther the distance from the object blocking the light to the surface of projection, the larger the silhouette (they are considered proportional). Also, if the object is moving, the shadow cast by the object will project an image with dimensions (length) expanding proportionally faster than the object's own rate of movement. The increase of size and movement is also true if the distance between the object of interference and the light source are closer. This, however, does not mean the shadow may move faster than light, even when projected at vast distances, such as light years. The loss of light, which projects the shadow, will move towards the surface of projection at light speed.

Although the edge of a shadow appears to "move" along a wall, in actuality the increase of a shadow's length is part of a new projection that propagates at the speed of light from the object of interference. Since there is no actual communication between points in a shadow (except for reflection or interference of light, at the speed of light), a shadow that projects over a surface of large distances (light years) cannot convey information between those distances with the shadow's edge.[6]

Visual artists are usually very aware of colored light emitted or reflected from several sources, which can generate complex multicolored shadows. Chiaroscuro, sfumato, and silhouette are examples of artistic techniques which make deliberate use of shadow effects.

During the daytime, a shadow cast by an opaque object illuminated by sunlight has a bluish tinge. This happens because of Rayleigh scattering, the same property that causes the sky to appear blue. The opaque object is able to block the light of the sun, but not the ambient light of the sky which is blue as the atmosphere molecules scatter blue light more effectively. As a result, the shadow appears bluish.[7]

A shadow occupies a three-dimensional volume of space, but this is usually not visible until it projects onto a reflective surface. A light fog, mist, or dust cloud can reveal the 3D presence of volumetric patterns in light and shadow.

Fog shadows may look odd to viewers who are not used to seeing shadows in three dimensions. A thin fog is just dense enough to be illuminated by the light that passes through the gaps in a structure or in a tree. As a result, the path of an object's shadow through the fog becomes visible as a darkened volume. In a sense, these shadow lanes are the inverse of crepuscular rays caused by beams of light, they're caused by the shadows of solid objects.

Theatrical fog and strong beams of light are sometimes used by lighting designers and visual artists who seek to highlight three-dimensional aspects of their work.

Oftentimes shadows of chain-linked fences and other such objects become inverted (light and dark areas are swapped) as they get farther from the object. A chain-link fence shadow will start with light diamonds and shadow outlines when it is touching the fence, but it will gradually blur. Eventually, if the fence is tall enough, the light pattern will go to shadow diamonds and light outlines.

In photography, which is essentially recording patterns of light, shade, and color, "highlights" and "shadows" are the brightest and darkest parts, respectively, of a scene or image. Photographic exposure must be adjusted (unless special effects are wanted) to allow the film or sensor, which has limited dynamic range, to record detail in the highlights without them being washed out, and in the shadows without their becoming undifferentiated black areas.

On satellite imagery and aerial photographs, taken vertically, tall buildings can be recognized as such by their long shadows (if the photographs are not taken in the tropics around noon), while these also show more of the shape of these buildings.

Shadow as a term is often used for any occlusion or blockage, not just those with respect to light. For example, a rain shadow is a dry area, which with respect to the prevailing wind direction, is beyond a mountain range; the elevated terrain impedes rainclouds from entering the dry zone. An acoustic shadow occurs when a direct sound has been blocked or diverted around a given area.

An unattended shade was thought by some cultures to be similar to that of a ghost. The name for the fear of shadows is "sciophobia" or "sciaphobia".

Chhaya is the Hindu goddess of shadows.

In heraldry, when a charge is supposedly shown "in the shadow" (the appearance is of the charge merely being outlined in a neutral tint rather than being of one or more tinctures different from the field on which it is placed), it is technically described as "umbrated". Supposedly, only a limited number of specific charges can be so depicted.[citation needed]

Shadows are often linked with darkness and evil; in common folklore and modern graphic novels, like shadows who come to life, are often evil beings trying to control the people they reflect. The film Upside-Down Magic features an antagonistic shadow spirit who possesses people.

Scientists from the National University of Singapore presented a shadow-effect energy generator (SEG), which consists of cells of gold deposited on a silicon wafer attached on a plastic film. The generator has a power density of 0.14 W cm2 under indoor conditions (0.001 sun).[8]

Non-diffuse lighting in outer space causes deep shadows

This photo of jasmine flowers has only soft shadows cast by diffused light

Shadow of a parent and child

Long shadow of a dead tree with its branches on dry fields, late afternoon

When the sun is low, shadows become long, and details get the wrong proportions.

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Shadow - Wikipedia

A Warzone shadow ban is a tricky thing to identify because it's hard to tell if you have been shadow banned or not. It's a way of dealing with cheaters and hackers which have been a big Call of Duty Warzone since its inception - basically put them all together and leave the normal players in peace. However, it looks sometimes innocent players, streamers and popular players have been shadow banned in Warzone too. Although it can be hard to tell given the rampart cheating problem in Warzone - are you in a shadow banned lobby full of hackers, or is it just a usual match. Here's everything you need to know about Warzone shadow bans including what it looks like when you are shadow banned and how to get unbanned in Warzone.

Warzone Numbers event| Call of Duty Warzone tips | Warzone Red Doors | Warzone Error codes | Is Warzone down? | Warzone Patch notes | Warzone best guns | Warzone best SMGs | Warzone best sniper

What is a Warzone shadow ban? Being shadow banned essentially means you're "banned", but you're not explicitly told that or given a ban message. That's because you aren't stopped from playing Call of Duty Warzone, but instead you get placed into special lobbies that are different from the usual game.

Essentially, every lobby you get put into while shadow banned will only consist of other players that have also been shadow banned. This is Activision's method of ensuring all cheaters and hackers are unable to ruin the game for legitimate players. There's no warning for this however, so it can take a while for cheaters to realise they've been hit with a shadow ban in Warzone.

If you think you may have received a Warzone shadow ban for one reason or another, there are certain clues you can look for to try and work it out. The most obvious of these is the long queue times you'll be facing thanks to the small pool of fellow shadow banned players. Of course, you could also be facing long queue times thanks to a slow internet speed, narrow search parameters, or another external factor, but it's something to consider if you're concerned you've been shadow banned.

Apparently, when you get shadow banned, your ping will skyrocket to north of 300. So if you're in a match, you have reason to believe you're at risk of a shadow ban, and your ping starts causing you some serious grief despite your internet connection seeming stable otherwise, then it's another clue.

Finally, and perhaps the damning clue of them all, is if you're coming up against an obscene number of hackers and cheaters in your matches. It goes without saying that if you find every death suspicious and you're struggling to get any kills, you might be playing in a shadow ban lobby. Or you're just incredibly paranoid.

False positives do happen with Activision's ban detection system. It sucks but if it has happened and your ban hasn't been automatically lifted after two weeks, you can use the official Activision ban appeal system to try and get it sorted. Now it goes without saying that if you were hacking in Warzone, you're highly unlikely to get unbanned, but you can give the appeal a shot nonetheless. Good luck!

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Warzone shadow bans explained | GamesRadar+

on 27th October 2021 @ 6.00pm

Donald Trump said his new social media venture, TRUTH Social, willchallenge the dominance of the Big Tech giants and go head-to-head with the leading platforms.

Trump Media & Technology Group (TMTG) is set to launch in beta next month before coming online for all users in early 2022.

Trump slammed a small group of self-righteous scolds and self-appointed arbiters for censoring Americans.

Trump wrote in a statement:

Last week, I announced the creation of a major new company that will challenge the dominance of the Big Tech giants and Big Media bosses.

For me, this endeavor is about much more than politics."

"This is about saving our country,he continues.

There will be no shadow-banning, throttling, demonetizing, or messing with algorithms for political manipulation."

"We will not be treating users like lab rats for social experiments, or labeling alternative views as 'disinformation,'"he adds.

And as everyone knows, weve seen a sitting president of the United States effectively silenced by a small oligarchy of tech titans and mainstream media corporations, Trump said.

The corruption of these platforms cannot be ignored.

"We have fallen far down the slippery slope of censorship in our country, and the topics that Americans are increasingly forbidden to debate are among the most important issues of our day.

Its a tremendously difficult set of challenges and I realized I might be the only person in America with the megaphone, the resources, the experience, and the desire to make it all happen."

"So with the same can-do spirit that has always allowed Americans to persevere, that is exactly what I am doing, Trump said.

Unlike with the Big Tech platforms, there will be no shadow-banning, throttling, demonetizing, or messing with algorithms for political manipulation.

"We will not be treating users like lab rats for social experiments, or labeling alternative views as disinformation."

"We will not silence our fellow citizens simply because they might be wrong or worse, because we think that Americans cant handle the truth.

Earlier this month, Trump filed a lawsuit against tech giant Twitter asking a federal judge to reinstate his account, which was removed earlier this year.

In the lawsuit filing, Trump argues that being banned from Twitter violates the First Amendment.

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Trump Vows No Shadow-Banning on His New Social Media ...

Deftly and unnervingly, all nine justices sidestepped that question and stuck to S.B. 8. Even Justice Clarence Thomas, perhaps the most antiabortion justice of them all, asked sensible procedural questions that revealed key weaknesses of S.B. 8. For instance, he asked the Texas solicitor general what is the civil injury in fact to the plaintiffs that the law was hoping to remedy. All Judd Stone, the Texas solicitor general, apparently could come up with was a scenario in which a pro-life person who finds out someone was having an abortion gets so upset that the injury suffered results in a tort of outrage. Thomas wasnt down with that. Forgive me, he said, but I dont recall an outrage injury.

The others followed suit. Does it matter that the bounty is $10,000 and not $1 million, as Roberts wondered? And given the procedural morass S.B. 8 has created, as Justice Elena Kagan put it, in the challenge brought by abortion clinics to the law, what should the Supreme Court fashion as the proper remedy? In the separate case by the Biden administration against Texas, does the Justice Department have limitless power to invoke that broad equity power to stop unlawful conduct whenever the government pleases, no matter the administration in charge, as Roberts asked? Or, at the request of the same federal government, is there precedent for allowing a judge to block the conduct of everyone in the country or the world [or] the cosmos, as Justice Neil Gorsuch seemed to worry might happen if the DOJ case were allowed to proceed?

These questions dont all have easy answers. And some of them, as is often the case in the gilded halls of the Supreme Court, were classic examples of justices playing devils advocate for extreme positions. A search for a limiting principle, as Roberts and other institutionalists who are afraid the floodgates will open, love to say. As for courts having the power to block anyone wishing to cash in on S.B. 8, Elizabeth Prelogar, the Biden administrations newly confirmed solicitor general, had this to tell Gorsuch, who suggested more than once that Merrick Garland may have overreached by suing Texas and all of its officers, employees, and agents, plus anyone else who ever invokes S.B. 8. In the history of the United States, Prelogar said, no state has done what Texas has done here.

A highly anticipated moment of the hearing came when Jonathan Mitchell, whom the New York Times identified as the architect of S.B. 8, took the lectern. The Supreme Court allowed him some time to arguenot to defend his own handiwork, but rather as the lawyer for a group of antiabortion private citizens contemplating lawsuits under S.B. 8. Kagan, earlier in the hearing, had already signaled disdain for Mitchell and his allies when she said that some geniuses had come up with a way to get around an earlier ruling that, in another era, might have stopped a law like S.B. 8 in its tracks. But none of the liberal justices pounced on Mitchell as may have been anticipated. And Mitchells own presentation, a little more than 10 minutes long, largely came and went without fireworks or major revelationsother than Mitchells clear antipathy towards the Justice Departments position.

The most important question of all may have come from Justice Stephen Breyer, who asked what would happen if what Texas patients are facing today were akin to Arkansas in 1957a dark time in our nations history, years after Brown v. Board of Education, when states were openly flouting that ruling and refusing to integrate their schools. What if someone wrote a bounty law to sue anyone who brings a Black child to a white school? Breyer wondered. Stone, the Texas lawyer defending S.B. 8, began to answer that Congress wouldve responded with a law to allow the federal government to intervene, as the Justice Department is intervening today to block the bounty hunter law. But Breyer wasnt having it. Congress was no help. I mean, believe me, they did nothing, or, if they did something, Im unaware of it, he said.

And thats the key weakness of S.B. 8. The reality remains that if that monstrosity is allowed to remain on the books, then theres no telling what other monstrosities are possible in the various states down the line. Itll be back to the 1950s. And Congress wont be able to stop them. Justice Sotomayor named a few of the likely consequences: Blue states could defy the Supreme Courts gun-rights decisions and allow anyone to drag to court law-abiding gun owners. Or states opposed to gay rights could defy the Supreme Courts pro-LGBTQ rulings and serve papers on anyone having consensual sex or officiating same-sex weddings. The sky is the limit. That would be an intolerable state of affairs and it cannot be the law, concluded Prelogar toward the end of the marathon session. Our constitutional guarantees cannot be that fragile. And the supremacy of federal law cannot be that easily subject to manipulation.

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An Intolerable State of Affairs: The Supreme Court Is Looking Awfully Skeptical of Texass Antiabortion Law - Vanity Fair

You dont have to denounce Trump, Russ Schriefer, a strategist who has advised the campaigns of Mitt Romney, Chris Christie and other Republican luminaries, told me. But you do have to create your own identity.

He noted that when Larry Elder, a Republican, failed in his recall bid against Californias Democratic governor, Gavin Newsom, he failed to do that, which gave Democrats a bit of a false positive, making them think that if we just say Trump, Trump, Trump, the Republican will start dropping like a stone. Youngkins Democratic opponent, Terry McAuliffe, shouted Trump, Trump, Trump until he was hoarse, but, Schriefer said, there was a very artful dance that Youngkin was successfully able to execute.

That dance, though, hinged on a factor that got inadequate attention in the final weeks and days of his campaign: Trump allowed it. The former president was uncharacteristically even-tempered and restrained. Instead of taking offense at the distance that Youngkin kept from him, instead of taking the bait when journalists pointed that out, he professed to be unbothered. He claimed amity and mutual respect between the two of them.

He saw that Youngkin had a chance to win, undoubtedly wanted to be associated with that victory and apparently understood the upside of giving Youngkin a pass on flamboyant Trump idolatry. For Republicans accustomed to needier behavior from the monarch of Mar-a-Loco, that was one of the most encouraging developments of all.

Trump wasnt the only variable in play. He probably wasnt the main one, to the frustration of McAuliffe, who was as adamant about mentioning Trump as Youngkin wasnt. Thats where the Trump-related lessons of Virginia have limits. The takeaway here is as much about Democrats who, after all, have control of the White House and Congress as it is about Republicans. Or, rather, its about Republicans ability to pin the constipation in Congress, the perpetuation of pandemic-related restrictions and a range of economic setbacks on Biden, Chuck Schumer and Nancy Pelosi. Being out of power has its perks, and chief among them is the ease of grousing versus governing.

Gas prices have gone up, theres inflation across the board, there are turkey shortages for Thanksgiving and predictions of delayed Christmas presents, and the Democrats response is, Dont worry, were close to banning methane, Corry Bliss, a prominent Republican strategist who lives in Virginia, said when I spoke with him on Tuesday. Theres a tremendous disconnect.

Blisss comments were a preview of Republicans talking points for the midterms, and my conversation with him was just as telling in another way: Every time I brought Trump into the discussion, he ushered Trump out of it, but never with a hint of disrespect or scintilla of disdain.

Excerpt from:

Opinion | How Youngkin Made Use of Trump in His Virginia Win - The New York Times

Ahead of Diwali, which will be celebrated under the shadow of the pandemic, the Maharashtra government on Wednesday issued Standard Operating Procedures (SOPs) to contain the spread of COVID-19. Diwali will be celebrated between November 2 (Dhanteras) and November 6 (Bhai Dooj).

The Uddhav Thackeray-led Maha Vikas Aghadi government has urged citizens to avoid bursting crackers to curb noise and air pollution which could pose a problem for coronavirus patients. A government release appealed for the subdued celebration of Diwali, like that of other festivals since the virus outbreak. Social distancing norms should be followed, the guidelines reminded.

Although the use of firecrackers is not banned in the state, the government has urged citizens to avoid bursting crackers.

The state government guidelines said: "Those affected by COVID-19 are likely to be troubled directly due to the air pollution caused by bursting of firecrackers. Considering this, people should avoid bursting firecrackers this year. Instead, they can light lamps on a big scale and celebrate the festival."

It has also urged people not to overcrowd markets for Diwali shopping.

Meanwhile, several states have banned the use of firecrackers. The Karnataka government on Saturday issued an order allowing the sale and bursting of only green crackers during this Deepavali and advised people to strictly adhere to COVID-19 norms.

The West Bengal Pollution Control Board (WBPCB) on Saturday issued a notification banning the sale and use of all kinds of fireworks during Kali Puja, Diwali and other festivals this year following an order of the Calcutta High Court.

Here's what the Mumbai mayor said:

Mumbai mayor Kishori Pednekar on Tuesday appealed to citizens to keep a check on noise and air pollution levels while bursting firecrackers during Diwali.

Extending her Diwali greetings, the mayor in a video message said monitoring agencies have claimed that noise and air pollution levels go up during the festive season.

"Crackers are an integral part of Diwali festivities and they should be. However, while bursting crackers, people must keep a check on noise and air pollution levels," Pednekar said.

The mayor further stated that senior citizens, children and patients face a lot of problems due to the crackers, and hence, people should ensure that they are not troubled.

Last year, the Brihanmumbai Municipal Corporation (BMC) had banned fireworks in the city during Diwali, and permitted use of mild firecrackers at private premises on Laxmi Pujan.

(With agency inputs)

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Diwali 2021: Are firecrackers banned in Mumbai and Maharashtra? Click here for green cracker rules - Free Press Journal

Tuesday marks the end of what has been a highly contentious campaign for Virginia governor. And on Monday, Democrat Terry McAuliffe and Republican Glenn Youngkin made their last pitch to Virginia voters on WTOP.

Tuesday marks the end of what has been a highly contentious campaign for Virginia governor, between Democrat Terry McAuliffe and Republican Glenn Youngkin.

And on Monday, the pair who, according to recent polls, are in a dead heat made their last pitch to Virginia voters during interviews with WTOP.

Youngkin, who has spent much of his career working for a private-equity firm, spoke with Shawn Anderson and Hillary Howard as he wrapped up a 10-day bus tour around the state.

Republican candidate Glenn Youngkin makes his case to votes during his interview on WTOP.

The major focus of the race has been critical race theory, an academic framework that examines how systemic racism is ingrained in the history of America. Its not taught in Virginia public schools. But over the last few months, it has fueled conservative anger nationwide.

When asked to respond to Democrats accusations that Republicans have distorted the issue to stoke racial anger and resentment, Youngkin accused McAuliffe of making up things.

The reality is that the beginnings of critical race theory in Virginia School started during his administration, he said.

Youngkin also denied that he wanted books like Toni Morrisons Beloved banned, even though the Nobel-winners book is involved in a campaign ad.

That ad concerned McAuliffes opposition as governor to a bill that would have forced schools to warn parents if their children are assigned books with explicit content. He vetoed the bill in 2016.

Youngkin argued it shows the former governor is out-of-touch. This is why we see such a disconnect between where Terry McAuliffe is and where, candidly, the vast majority of Virginia parents are, which is all they want is to have a say in their childs education.

Another recurring theme of the race has been the shadow of former President Donald Trump, who was scheduled to take part in a telerally for Youngkin Monday night.

When asked how close he is to Trump, Youngkin replied well, not terribly.

Democratic candidate Terry McAuliffe makes his case for voters' support during an interview with WTOP.

Earlier on WTOP, though, McAuliffe pointed out that Youngkin has received multiple endorsements from the former president.

I am happy to remind voters about Donald Trump, the Democrat said. He was the most divisive president weve ever had his racist dog whistles and tweets and misogynist tweets every day. Were better than that. As a nation, we are better than this.

McAuliffe also defended his education record when he first served as governor from 2014 to 2018, and emphasized his plans to raise teacher pay above the national average and getting at-risk 3- and 4-year-olds into prekindergarten.

His education plan is banning books, McAuliffe said of Youngkin, and, No. 2, talk about critical race theory. Its racist dog whistles. Its getting parents against parents, parents against teachers, using our children as political pawns.

McAuliffe also challenged the narrative that the race has gotten tighter in recent weeks.

This race has always been the same, he said. This race has not moved really in the last four or five months. Its always been a 1-to-3-point race.

Turnout, he said, is key. Were not persuading anybody, he said of himself and his opponent.

Its about getting your voters to the polls.

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McAuliffe, Youngkin make their final pitches to voters on WTOP - WTOP