Rules of the FYKOS Correspondence Competition

On this page you will find the full text of the rules for the FYKOS Correspondence Competition.

Registration

• Participation in the FYKOS Correspondence Competition (hereinafter referred to as "FYKOS") requires prior registration in the submission system at https://db.fykos.cz/.
• By registering for FYKOS, a participant confirms that they have read these Rules and undertakes to follow them.
• FYKOS is an individual competition.
• Each participant must be a high-school student, a primary-school student, or their respective equivalent.
• It is possible to register for a given year of the competition at any time during its course, but no later than the submission deadline of the last series.
• Participants are obliged to provide truthful information upon registration and, should it change, to update it or notify the organizers of the change without undue delay.
• By registering for the competition, a participant agrees to the publication of their results in the form of basic information (their name, surname, category, school, and points) in the results list in both print and digital outputs.

Designation into Categories

• The competition is held in four categories, which correspond to the four years of high school study, that is, study at level 3 of the ISCED 2011 classification. In the Czech Republic, this typically means a four-year high school.
• A participant is assigned to a category based on their expected school year of high school graduation. A participant who is, at the time of the competition, in the final (i.e., graduating) year of high school competes in the 4th-year category. A participant in the penultimate year competes in the 3rd-year category, and so on.
• Pupils of primary schools and of the corresponding lower years of multi-year grammar schools are assigned to the 1st-year category.
• In ambiguous cases, a participant's category is determined by the head organizer or an organizer authorized by them. The organizers reserve the right to adjust a participant's assignment to a category if they find that the information provided upon registration is inaccurate.
• All categories share the same set of problems.
• Each category has its own results list.

Competition Format

• One year of FYKOS consists of six series, each of which contains eight problems.
• Each series contains two easy theoretical problems, three difficult theoretical problems, one open problem, one experimental problem, and one serial problem.
• The statement of the open problem is typically open-ended and calls for a detailed physical analysis of the situation posed.
• The experimental problem requires carrying out the assigned experiment and processing the measured data.
• The serial problems within a single year are all devoted to a single, more advanced topic. Each serial problem is published together with an installment of the serial, an instructional text that introduces the theory needed to solve the problem.
• Problem statements are published progressively, series by series, in the Problems section of the website https://fykos.org/ (hereinafter referred to as the "FYKOS website").
• If a serious issue is found in the statement of a problem, the organizers reserve the right to modify that problem or eliminate it from the competition, without any entitlement to compensation. Participants will be informed of such changes on the main page of the FYKOS website.
• In the case of a less serious error in a problem statement or an issue in the grading or the results, the organizers reserve the right to make an appropriate correction. Such changes will be made on the relevant pages of the FYKOS website, and the participants concerned may be informed of them individually.

Solution Requirements

• The competition languages are Czech, Slovak, and English. Solutions written in any other language will not be graded.
• The maximum length of the solution to a single problem is 12 standard pages (approx. 21,600 characters). Parts of a solution exceeding this limit need not be taken into account.
• Every solution must include a clearly explained line of reasoning, not merely the result. The reasoning must make clear which physical considerations and assumptions the participant used and which key steps of the derivation they carried out.
• For an experimental problem, the solution must further include a description of the apparatus used, the measurement procedure, the measured data, and an evaluation of the measurement uncertainties; more detailed methodological instructions are given in the Guide to FYKOS Experimental Problems, available on the FYKOS website.
• When solving the problems, participants are permitted to use any literature and any internet sources. When using someone else's texts, figures, data, calculations, procedures, or other materials, the participant must properly cite the source. Verbatim reproduction of passages is admissible only to a reasonable extent and with a proper citation of the source.
• A participant must work out the solution to each problem independently.
• Minor consultations about the problems with other participants, teachers, and other people are permitted. A consultation must not amount to handing over a complete solution to a problem or a substantial part of it, systematically guiding the participant step by step, or having another person work out key parts of the solution.
• It is forbidden to present someone else's solution as one's own. This prohibition applies both to copying from other participants and to solutions, or substantial parts thereof, produced by another person or by a generative artificial intelligence tool, even if the source is cited.
• Generative artificial intelligence tools must not solve a problem for a participant or write up the solution. The use of these tools is governed by the Rules on the Use of AI, available on the FYKOS website.

Submission of Solutions

• Solutions are submitted through the submission system at https://db.fykos.cz/.
• The only accepted format is PDF in A4 size. A solution may be written up electronically, or it may be a scan of a handwritten solution. A scan of a handwritten solution must be legible and correctly oriented. Submitting a solution in any other format creates a risk that the solution or a part of it will be lost, for which the organizers accept no responsibility.
• The maximum size of a submitted file is 30 MB.
• The solution to each problem is submitted as a separate file; solutions to multiple problems cannot be combined into a single PDF.
• The first page of every solution must clearly state the problem number, the series number, and the participant's name. If a solution has more than one page, the participant's name must appear on each of them.
• A participant may submit solutions to any number of problems from a given series; it is not necessary to submit all of them. Individual problems may be submitted independently of one another.
• If a participant submits a solution to the same problem more than once, the last version submitted before the submission deadline is graded.
• Solutions must be submitted no later than the deadline stated for the given series. The official submission time is the timestamp recorded by the submission system. Solutions submitted after the deadline will not be graded, unless the organizers decide otherwise.
• The organizers reserve the right to postpone the submission deadline of a problem or of an entire series. Participants will be informed of such a change on the main page of the FYKOS website.

Grading and Awarding of Points

• The maximum score for each problem is given in its problem statement.
• Solutions are graded by designated graders. The grading assesses both the correctness of a solution and its compliance with the Solution Requirements.
• Partial solutions are graded as well; points are awarded for individual steps and considerations, not only for arriving at the correct result.
• For particularly high-quality solutions — for example, exceptionally original ones, unusually thorough ones, or ones that show deep physical insight — graders may award bonus points beyond the maximum score for the problem. The award of bonus points is a matter of the grader's expert judgment; there is no entitlement to bonus points.
• Solutions, or parts of them, need not be graded if they are illegible, written in a language other than a competition language, submitted after the deadline, or if they otherwise violate the Solution Requirements.
• After the grading of a given series is complete, participants can view their graded solutions in the submission system at https://db.fykos.cz/.
• If participants have any questions or comments regarding their graded solutions, they may contact the organizers at the email address fykos@fykos.org. The period for submitting comments is at least 14 days from the date on which the graded solutions of the last series are made available; the organizers will announce the exact deadline to participants via the email address provided upon registration. Comments will be considered and, where appropriate, reflected in the grading.

Competition Results and Prizes

• After each series has been graded, the current results lists are published on the FYKOS website.
• The overall ranking in each category is determined by the participants' total score across all series of the given year. Participants with an equal total score share the same rank.
• For participants in the 1st-year and 2nd-year categories, the points earned for problems 1 and 2 in each series count double in the results lists. No other point advantages apply.
• A successful solver is a participant who, in a given year, obtains at least half of the maximum number of points attainable in the 4th-year category (bonus points not included).
• The best participants may be rewarded, for example, with material prizes or with the opportunity to take part in some of the FYKOS events. Participants have no entitlement to material prizes or to any other rewards.

Breach of Rules

• In the case of a breach of these Rules, or of a reasonable suspicion of such a breach, the organizers may take this into account in the grading.
• Depending on the seriousness of the situation, the organizers may reduce the score of the solution concerned, not grade the solution concerned, remove points that have already been awarded, disqualify the participant from the competition, or restrict their participation in subsequent years of the competition or in other FYKOS events. The organizers also reserve the right to share information about rule violations with the organizers of other competitions and activities organized or promoted by the CUNI MFF, as well as with representatives of the participants' schools.
• Measures taken in response to a breach of these Rules are decided on by the head organizer or an organizer authorized by them.

Final Remarks

• The organizers reserve the right to make minor changes and clarifications to these Rules during the course of a year. Participants will be informed of any such changes on the FYKOS website.
• Any disputes and difficulties that are not covered by these Rules are decided on by the head organizer or an organizer authorized by them.
• These Rules were approved by the organizers of FYKOS and come into effect on September 1, 2026.