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Our Mission

Physics Forums aims to provide a community for students, scientists, educators or hobbyists to learn and discuss science as it is currently generally understood and practiced by the professional scientific community.

Our main focus is physics, but we also cater to other STEM fields including engineering, chemistry, biology, mathematics, etc.

STEM homework help for students is available, as well as academic and career guidance.

Terms of Service

Welcome to Physics Forums!

In an effort to maintain the integrity of this site and to provide a comfortable environment for people to communicate, we ask that you please follow these Guidelines when posting on this site. These guidelines are global and apply to every area of this site. Mentors may choose to enact specific guidelines for individual forums, which are to be taken as an extension to the global guidelines when posting and visiting that specific forum. These specific guidelines are usually sticky topics placed at the top of the specific forum.

Application and interpretation of these Guidelines is subject to the discretion of the Physics Forums Mentors (moderators). Posts that violate these Guidelines are routinely removed.

We reserve the right to close the accounts of persistent violators of these Rules of Conduct at any time and without warning.

All messages express the views of the author, and neither the owners of Physics Forums nor its developers will be held responsible for the content of any message.

Short Summary:

Most of the guidelines are common sense and basic courtesy. Other special guidelines are the following:

  • We wish to discuss mainstream science. That means only topics that can be found in textbooks or that have been published in reputable journals.
  • Homework must be posted in the homework forums and an attempt must always be provided. Furthermore, one must use the homework template.
  • Full solutions on a homework problem should never be given. Only hints and explanations are allowed.
  • Be civil, productive and aim for high quality of participation.

Mission Statement:

Our mission is to provide a place for people (whether students, professional scientists, or others interested in science) to learn and discuss science as it is currently generally understood and practiced by the professional scientific community. As our name suggests, our main focus is on physics, but we also have forums for most other academic areas including engineering, chemistry, biology, social sciences, etc.

General Posting Guidelines:
  • When posting a new topic, please select the forum that best relates to the subject matter of your topic. If you are unsure, contact a mentor or the admin.

  • Language:
    All posts must be in English. Posts in other languages will be deleted. Pay reasonable attention to written English communication standards. This includes the use of proper grammatical structure, punctuation, capitalization, spacing, and spelling. In particular, "I" is capitalized, there's a space after (but not before) a comma, a period, and other punctuation. Multiple exclamation marks are also discouraged. SMS messaging shorthand ("text-message-speak"), such as using "u" for "you", "plz" for "please", or "wanna" for "want to" is not acceptable.

  • Multiple Posting:
    Posting the same topic (or homework question) across multiple forums or multiple threads is considered spamming and is not allowed. (No cross-posting.)

  • Thread hijacks and off-topic posts:
    Do not hijack an existing thread with off-topic comments or questions--start a new thread. Any off-topic posts will be deleted or moved to an appropriate forum per administrator or mentor discretion.

  • Reopening Locked Thread:
    Do not re-post comments from a locked thread without explicit permission of a mentor.

  • Bumping
    Do not "bump" one of your threads to the top of a forum's thread list by posting a basically empty message to it, until at least 24 hours have passed since the latest post in the thread; and then do it only once per thread.

  • Fonts:
    When posting a new topic do not use the CAPS lock (all-CAPS), bold, oversized, non-standard, or brightly colored fonts, or any combination thereof. They are hard to read and are considered yelling. When replying in an existing topic it is fine to use CAPS or bold to highlight main points.

  • Replying to a Post:
    When replying to a post, please use the correct button! If you wish to quote a previous post in your reply, use the "Quote" button; if you do not, use the "New Reply" button. Do not use the "Report" button to reply to a post; this sends a message to the Mentors (moderators), and is normally used only to report spam or other posts that you think violate the Guidelines.

  • Quoting a Post:
    When you quote from a post, please delete large sections that are not directly relevant to your response, to make reading easier, but do not distort the original poster's meaning in the process. You may add colors or change the font of words or phases for emphasis, provided that you state explicitly that you have done so. Other forms of purposeful misquoting are dishonest and are not permitted.

General Contents Guidelines:

  • Please clearly state what you wish to discuss. In general, one should attempt to flesh out questions and arguments adequately enough that readers will have a good understanding of the issue.

  • Personal Information:
    Refrain from disclosing personal information about yourself or third parties, information such as hometown, real name, email address... The staff may edit out such information if posted. Also, do not post personal communications, such as emails or conversations, with third parties. Please see our privacy policy for more information.

  • Non-mainstream theories:
    Generally, in the forums we do not allow the following:
    • Discussion of theories that appear only on personal web sites, self-published books, etc.
    • Challenges to mainstream theories (relativity, the Big Bang, etc.) that go beyond current professional discussion
    • Attempts to promote or resuscitate theories that have been discredited or superseded (e.g. Lorentz ether theory); this does not exclude discussion of those theories in a purely historical context
    • Personal theories or speculations that go beyond or counter to generally-accepted science
    • Mixing science and religion, e.g. using religious doctrines in support of scientific arguments or vice versa.
    • Philosophical discussions are permitted only at the discretion of the mentors and may be deleted or closed without warning or appeal

    Links to web sites that fall in the categories listed above will be removed.

  • Acceptable Sources:
    Generally, discussion topics should be traceable to standard textbooks or to peer-reviewed scientific literature. Usually, we accept references from journals that are listed here:

    Use the search feature to search for journals by words in their titles. If you have problems with the search feature, you can view the entire list here:

    In recent years, there has been an increasing number of "fringe" and Internet-only journals that appear to have lax reviewing standards. We do not generally accept references from such journals. Note that some of these fringe journals are listed in Thomson Reuters. Just because a journal is listed in Thomson Reuters does not mean it is acceptable.

    References that appear only on (which is not peer-reviewed) are subject to review by the Mentors. We recognize that in some fields this is the accepted means of professional communication, but in other fields we prefer to wait until formal publication elsewhere. References that appear only on viXra ( are never allowed.

  • Speculative or Personal Theories:
    Physics Forums is not intended as an alternative to the usual professional venues for discussion and review of new ideas, e.g. personal contacts, conferences, and peer review before publication. If you have a new theory or idea, this is not the place to look for feedback on it or help in developing it.

    For further explanation of our policy on personal theories and speculative posts, and the history behind it, see the following entry in the Physics Forums FAQ:

  • Language and Attitude:
    Foul or hostile language will not be tolerated on Physics Forums. This includes profanity, obscenity, or obvious indecent language; direct personal attacks or insults; snide remarks or phrases that appear to be an attempt to "put down" another member; and other indirect attacks on a member's character or motives.

    Please treat all members with respect, even if you do not agree with them. If you feel that you have been attacked, and the moderators or mentors have not yet gotten around to doing something about it, please report it using the "Report" button. If you choose to post a response, address only the substantive content, constructively, and ignore any personal remarks.

    It is better to walk away from a possible confrontation and come back later with constructive arguments.

  • Attachments and Links:
    Images, material or links to images and or material whether real, satirical or implied depicting obscene, indecent, lewd, pornographic, violent, abusive, insulting, or threatening in nature are not permitted on this bulletin board. This includes Gifs or cartoons.

  • Religious Discussion:
    Discussions that assert the a priori truth or falsity of religious dogmas and belief systems, or value judgments stemming from such religious belief systems, will not be tolerated. As a rule of thumb, some topics pertaining to religion might be permissible if they are discussed in such a way so as to remain neutral on the truth of, or value judgments stemming from, religious belief systems. However, it is essential to use good judgment whenever discussing religious matters to ensure that the discussion does not degenerate into a messy dispute. If in doubt, err on the side of caution.

    Because of the complexity and ambiguity of this subject matter, there are no hard and fast moderation rules that apply over all possible cases. Ultimately, it is up to the administrators and mentors to decide what is appropriate and what is not on a case-by-case basis. Discuss religious matters at your own risk: Administrators and mentors retain the right to lock or delete any religious thread or post at any time without warning or explanation. All administrator and mentor action taken with regard to religious discussions will be final and will not be up for dispute.

    Religious proselytizing is strictly prohibited! PF is not the place to promote or discuss particular religious dogma.

  • Conspiracy Theories & Closed Topics:
    Discussion of conspiracy theories and certain perennial pseudoscience topics that have been "debunked" beyond any reasonable doubt are not allowed anywhere on the site. A list of such closed topics can be found in the post below.

  • Illegal & Dangerous Activities:
    Explicit "how to" discussions of illegal and/or dangerous activities, or posts advocating such activities, are prohibited; such as: how to make explosives, manufacture crack, steal software, hack into the CIA, ...

    Additional details regarding discussion of controlled substances and chemicals can be found in the Chemistry Forum Guidelines.

  • Legal and Health Implications:
    Physics Forums reserves the right to remove and block discussion where there is plausibility that discussion may lead to litigation or affect ones health.

  • Copyright Violations:
    Copyright infringement is illegal. Physics Forums will adhere to the law to the best of its ability. Never post an article in its entirety. When posting copyrighted material, please use small sections or link to the article. When posting copyrighted material please give credit to the author in your post.

    Solicitations for copyrighted materials of any form will not be permitted. Posting links to unauthorized downloads of copyrighted material will not be permitted. Advertisement of locations where copyrighted materials may be obtained will not be permitted.

  • Soliciting:
    Soliciting or offering financial payment for any reason is strictly prohibited. Asking for interviews, members to join a group, cause or website is also prohibited.

  • Advertising & Spam:
    Advertising for personal gain of any kind is not permitted in any forum. Commercial spam will result in an immediate ban. Posting science website links will be permitted occasionally, but will be dealt with on a case by case basis.

Homework Guidelines
  • Posts Belong in the Homework Forum
    Any and all high school and undergraduate homework assignments or textbook style exercises for which you are seeking assistance are to be posted in the appropriate forum in our Homework & Coursework Questions area--not in blogs, visitor messages, PMs, or the main technical forums. This should be done whether the problem is part of one's assigned coursework or just independent study. The reason for this is that the scientific and mathematical sections of Physics Forums are to be reserved for discussions and not academic assistance. Since graduate level assignments are meant to be more thought provoking (and hence more worthy of discussion), graduate level questions will be allowed in the relevant part of the main section of PF, provided that the graduate student attempts the problem and shows his work.

  • Attempts are mandatory
    You MUST show that you have attempted to answer your question in order to receive help. You MUST make use of the homework template, which automatically appears when a new topic is created in the homework help forums. Once your question or problem has been responded to, do not go back and delete (or edit) your original post.

  • Cheating
    We do not support cheating in any form: Do not ask for solution manuals, answers to exams, or instructor's manuals. Every school and instructor has their own policies or honor codes on what constitutes cheating, and it is up to the individual student to adhere to those policies when seeking help here. If you are in doubt as to whether you are permitted to seek help, consider erring on the side of caution and not asking for help.

  • Giving Full Answers:
    On helping with questions: Any and all assistance given to homework assignments or textbook style exercises should be given only after the questioner has shown some effort in solving the problem. If no attempt is made then the questioner should be asked to provide one before any assistance is given. Complete solutions can be provided to a questioner after the questioner has arrived at a correct solution. If the questioner has not produced a correct solution, complete solutions are not permitted, whether or not an attempt has been made.

More information on the Homework Guidelines can be found in our Homework Forums:

Moderating and Disciplinary Actions
  • The Physics Forums Online Community is moderated by volunteers on a regular basis and we ask that you please respect their efforts. The list of current mentors can be found here.

  • Reporting Violations:
    If you witness a posting that violates these guidelines, please click the "Report" button, which can be found on the bottom left of the post. This will send a message to the Mentors and Admin, who will take action as they deem appropriate. Physics Forums cannot guarantee that any action will be taken as a result of your request. Please refer to this Disclaimer page from time to time for any updates Physics Forums may make to it.

  • Contacting Mentors:
    When contacting the owner or a specific mentor please make use of our Private Message system or email us. Do not post a topic in a forum regarding your situation.

    If you have a question or comment about how a specific thread or post has been moderated, please use the "Report" button. If you have more general questions or comments about Physics Forums' moderation policies, it may also be appropriate to start a thread in the Feedback & Announcement forum. Please refrain from posting questions or comments about Physics Forums' moderation policies and actions in any other forum.

  • Disciplinary Action:
    A member may be issued either a notice or an infraction if deemed warranted by an admin or mentor (usually from guideline noncompliance). Infractions range from 1 to 10 "points", depending on the severity of the violation; notices carry no points. If a member accrues 8 or more infraction points, he or she will be automatically banned from Physics Forums for a period of 10 days. If a member receives any infraction after having returned from a temporary ban, that member will then be banned permanently. Obvious, incorrigible spamming or trouble making will be met with a permanent ban.

  • Appealing an Infraction:
    If you feel an infraction is undeserved you may click the "Report" button on the infraction notice and explain why you do not feel the infraction was deserved. This will bring the issue before the rest of the Mentors who will discuss the matter internally and respond appropriately, which may include an action or message which is not visible to you. The Mentors decisions are final. Hostility, insults, or other rule-violations in the Report may result in additional infractions.

  • All messages express the views of the author, not necessarily the views of the forum owners. Members grant Physics Forums non-exclusive rights for the content they post. The owners and mentors of Physics Forums reserve the right to remove, edit, move or close any thread for any reason. This is a manual process, however, so please realize that we may not be able to remove or edit particular messages immediately. This policy goes for member profile information as well.

  • Gold Members:
    Certain categories of members (gold members, Mentors, etc.) may use automatic signatures that can be set via the member's control panel. These cannot contain images, must be no longer than four lines, must not conflict with PF's rules for content, and must not link to sites that conflict with those rules. Other members must not use signatures, including manually-appended ones.

  • Deleting Accounts:
    Please see our privacy policy for information of removing your account

  • Deleting Posts:
    Normally, we remove or edit posts only if they violate these Guidelines. You should consider your posts and threads as permanently available for everyone's benefit. If you want us to make an exception (e.g. a question that has not yet received any responses, or a post that contains personal identifying information), you may use the Report button on the post to request action.

  • Multiple Accounts:
    We allow only one account/username per person. Multiple accounts are not allowed (no sockpuppets). Similarly, only one person may use each account/username. Do not share accounts.

  • Site Advertising:
    Google Ads are used throughout the website as a means to generate revenue. Please do not abuse the ads and only click on them if you are genuinely interested. Physics Forums does not support or endorse any of the Google Ads. We encourage members to report crackpot ads to a staff member.

  • Conversations (PMs):
    If exclusively personal contact is needed, use the Conversation system. Conversations are NOT to be used to seek assistance with homework assignments or textbook exercises--post such questions in the appropriate forum in our Homework & Coursework Questions area. The administrator reserves the right to, and can, view all Conversation messages. Conversations are removed after one year has passed since the last reply.

  • Use of this Forum and your comments is not a right. It is a privilege granted you by Physics Forums under the terms of this agreement and can be revoked at any time without warning.

  • In accordance with the privilege of using this Forum granted you by Physics Forums, we request that you abide by the terms and conditions of our Rules of Conduct when using the Forum. We reserve the right to change the Rules of Conduct at any time.

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