Performance on a time production task, heart rate, and subjective responses were studied in twelve male sujects given oral doses of marijuana (0.7 mg of delta-9-tetrahydrocannabinol/kg), ethanol (1.0 ml/kg), and placebo, on three testing days which were each separated by 1 week. Orders were balanced across subjects and testing conditions were double-blind. Compared to ethanol and placebo, marijuana induced a significant under-production of time intervals, suggesting an acceleration of the internal rate of time perception. The onset of this acceleration of time sense in which geophysical time seemed to pass slowly corresponded with the characteristic increase in heart rate and the onset of the subjective feelings of drug effects. Initial phases of alcohol intoxication were associated with the opposite effects on the time production task. These findings replicate previous work and indicate that an easily administered time production task provides a consistent, non-motor measure of acute marijuana intoxication and also reflects ethanol intoxication.

The aim of this work is to review the concepts of time in quantum field theory and general relativity to show their incompatibility. We prove that the absolute character of Newtonian time is present in quantum mechanics and also partially in quantum field theories which consider the Minkowski metric as the background spacetime. We discuss the problems which this non-dynamical time causes in general relativity, a theory characterized by a local dynamical spacetime.

Description An atom interferometer measures the quantum phase due to gravitational time dilation In Einstein’s theory of general relativity, gravity is a manifestation of spacetime curvature. As predicted by general relativity and confirmed by numerous measurements, clocks moving at different velocities or located in different regions of a gravitational field tick at different rates (1), a phenomenon known as relativistic time dilation. Under appropriate conditions, time dilation can affect the oscillation phase of quantum waves and give rise to a measurable effect in interference experiments. On page 226 of this issue, Overstreet et al. (2) present an atom interferometry experiment in which this effect has been measured for gravitational time dilation. In addition to the importance of the results for fundamental physics, the methods used can lead to more accurate measurements of Newton’s gravitational constant, which parametrizes the strength of the gravitational interaction and is by far the least accurately known of all fundamental constants (3).

Socioemotional selectivity theory (SST) is a life-span theory of motivation grounded in the subjective awareness of human mortality. The cardinal postulate is that time horizons shape the relative priority placed on emotionally meaningful and knowledge-seeking goals. Because goals are always set in temporal contexts, and time left in life is inversely related to chronological age, SST predicts systematic age differences in goal pursuit. The theory has garnered considerable empirical support. In this paper, we consider the role of age-related time acceleration on goal setting and argue that it may interact with the more gradual age-related changes in time horizons presumed in SST. If so, the favoring of emotionally meaningful goals may follow an exponential (as opposed to linear) function across adulthood.

Research in the area of human sub-second-to-second timing has uncovered that emotional stimuli can influence our subjective timing, with much research highlighting that stimuli portraying high arousal negative emotions (for example, images of angry faces) cause a subjective lengthening effect, based on a potential fight or flight response. Further research has shown that in order for this effect to occur, the individual needs to be able to emulate the emotion that they have seen, suggesting that responses differ dependant on whether the individual is timing an emotional stimulus, or the individual is emotional while timing a neutral stimulus. Research in the area of social psychology has previously highlighted a link between social exclusion (peer rejection) and time distortion at the minute-to-multiple-minute range, with social exclusion causing a subjective lengthening effect of duration, supposedly due to cognitive deconstruction and emotional numbing. The current study aimed to investigate this further by examining the impact of peer rejection on sub-second-to-second timing. Participants completed a bisection task and were subsequently made to feel either rejected, or accepted by their peers. After this intervention stage, they again completed the bisection task. It was hypothesised that those who were rejected would experience subjective lengthening of duration, whereas those who were accepted would experience subjective shortening of duration. These hypotheses were supported. Implications and limitations of the study are also discussed.

In this study we examined whether the exposure to speed-altered audio clips of speech-like stimuli can distort systematically the subjective sense of time. Participants listened to stimuli of varying durations and speeds and reproduced their durations. Results revealed that both speed and actual duration influenced the length of reproduced durations. In particular, participants reproduced durations as longer when they listened to fast compared to slow speech-like stimuli of the same actual duration. In addition, the reproduced durations of long stimuli deviated more from their veridical durations compared to those of short stimuli. Notably, a significant interaction indicated that the effect of speed was greater for stimuli of short than of long actual durations. We argue that listening to fast speech-like stimuli speeds up the pacemaker component of the internal clock, leading to overestimation of the actual duration. The implications of these findings for the theories of time perception are discussed.

Abstract Background: The hypothesis that metabolic rate is inversely correlated with lifespan has long been debating. Another area of controversy is an evidence of a relationship between metabolic rate and time perception, and aging. Aim: to study the impact of overweight and food intake on metabolic rate, time-flow perception, chronic diseases, aging, lifespan; difficulties in weight loss. Methods: Design: a systematic review. Setting and Participants: Web of Science, Scopus, Science Direct, Kopernio, PubMed, Mendeley were searched for articles published from January 1979 until March 2020. The study bases on a viewpoint supported by a systematic literature review of 3612 articles published worldwide. Results: In total, 107 full-text articles were assessed for eligibility. From them, 25 articles were excluded with reasons. Overweight and food intake are the main causes of accelerating metabolic rate. By age, the body should less calorie intake due to decreasing metabolic rate. Body capability to gain weight is integral indicator of body energy reserve that depletes after weight gain. Increased metabolic rate creates a delayed time-flow perception and accelerates aging. Metabolic rate and lifespan are inversely correlated. Weight loss is a good tool to delay aging and increase lifespan. Very-low-calorie diets and to manage metabolic intoxication should use at weight loss. Conclusions: The findings support overweight with overeating increases metabolic rate that in turn delays time-flow perception, increases disease, accelerates aging, limits lifespan. For weight loss has to manage a very-low-calorie diet. Page 4/19 further studies retrieved for inclusion. Two researchers independently assessed and then reached an agreement on the included studies and the extracted data. All types of studies were included. Results And Discussion In the initial search, 3612 relevant articles were identied. 208 records after duplicates were removed. After the titles, abstracts, and texts were evaluated, 1151 articles were excluded (Fig. 1). In total, 107 full- text articles were assessed for eligibility. From them, 25 articles were excluded for the following reasons: twelve articles were excluded because they did not distinguish obesity from overweight; thirteen articles were excluded because they did not provide aging process and lifespan. Therefore, the nal sample comprised of 82 articles. Body mass, Food intake, Metabolic rate Basal metabolic rate (BMR) represents 75–80% of a total daily energy expenditure, and only 20–25% of a total energy expenditure is used for external work as physical and mental activity. (3, 4, 16) Therefore, BMR can imply MR as an indicator of the amount of energy expenditure per unit time. BMR of people with the same weight may differ by up to 25%. (17) For instance, in tropical populations, BMR is 15–20% lower compared to Europeans and Americans. (18) Overweight can change BMR on 20– 50%. (19) The largest part of BMR spends on food intake and digestion. On average, a 100-kcal surplus in daily energy expenditure and positive one percent shift in 24-hour respiratory quotient were associated with independent increases in ad libitum food intake of approximately 175 and 204 kcal/day, respectively, indicating that both the Page 9/19 kilogram overweight deprives  ≈  50 kcal/day of daily energy expenditure. (43) Overweight shortens lifespan, and weight loss increases it. (44) Overfat gain is unfavorable process for body energy. Overweight increases the total pool metabolites. (42, 45) Overweight reduces tolerance to physical/mental stress. (9) For each 100-kcal/day increase in energy expenditure, the mortality risk increases by 1.3. Higher MR for 24-hour energy expenditure predicts early mortality and aging. (46) Overweight and increased MR cause faster body aging. Energy expenditure depends on bodyweight. The heavier the body, the more energy he expends for living. (19, 47) Obesity signicantly increases energy expenditure. The highest amount of metabolism is expended to ensure nutritional (digestive) and reproductive metabolism. (48) Hyperactive sex reduces the total body energy that shortens lifespan. (49) Sex hormones play energetic role. (50) Sexual intercourse decreases sex hormones. The body makes an extra effort to restore the sex hormones reserve. (51) Overweight, Metabolic rate, Diseases, Time-ow perception Every disease increases in MR. (52) Patients with overweight expends more energy than healthy overweight people. (53) Every sick person has a delayed TFP. (54) Sick has more complaints related to impatience to achieve outcomes and rush events. Delayed TFP is associated with increase in MR in patients. (30, 55) Increased blood pressure, heart rate, respiratory rate, local/overall temperature, sweating, synthesis of enzymes/hormones, immunological system activation, secretions (sputum, sweat, urine, feces, etc.) indicate on increased MR. Every sick person has a higher MR and expends more own vital energy than healthy. (56) Every tired person has delayed TFP as a sick. Both are too impatient to achieve results, rush events. Overweight correlates with onset/development diseases such as diabetes mellitus, hypertension, allergic and inammatory diseases, urolithiasis and cholelithiasis, liver brosis, and tumor. (1, 57) Individual bodyweight, Potential body energy, Lifespan To accumulate fat mass ability is one of the basis to survive at food deciency. Food deciency accompanied the humankind continuously. Currently, the survival ability leads to obesity-epidemic. (1, 19) Every person has own individual bodyweight. Normal bodyweight is when the body does not suffer from any diseases. The more potential the body has, the more weight he can gain. Weightgain is limited due to body potential. Weight limit is when weight cannot increase, and when weight stables at the highest point of weightgain that is ‘terminal bodyweight’. Bodyweight is an integral indicator of body energy.

Time is the continuous progression of existence that occurs in an apparently irreversible succession from the past, through the present, and into the future Time is the continuous progression of existence that occurs in an apparently irreversible succession from the past, through the present, and into the future. Time dictates all forms of action, age, and causality, being a component quantity of various measurements used to sequence events, to compare the duration of events (or the intervals between them), and to quantify rates of change of quantitie Time is the continuous progression of existence that occurs in an apparently irreversible succession from the past, through the present, and into the future. Time dictates all forms of action, age, and causality, being a component quantity of various measurements used to sequence events, to compare the duration of events (or the intervals between them), and to quantify rates of change of quantities in material reality or in… Time has historically been closely related with space, the two together merging into spacetime in Einstein's special relativity and general relativity. According to these theories, the concept of time depends on the spatial reference frame of the observer, and the human perception, as well as the measurement by instruments such as clocks, are different for observers in relative motion. For example, if a spaceship carrying a clock flies through space at (very nearly) the speed of light, its crew does not notice a change in the speed of time on board their vessel because everything traveling at the same speed slows down at the same rate (including the clock, the crew's thought processes, and the functions of their bodies). However, to a stationary observer watching the spaceship fly by, the spaceship appears flattened in the direction it is traveling and the clock on board the spaceship appears to move very slowly. On the other hand, the crew on board the spaceship also perceives the observer as slowed down and flattened along the spaceship's direction of travel, because both are moving at very nearly the speed of light relative to each other. Because the outside universe appears flattened to the spaceship, the crew perceives themselves as quickly traveling between regions of space that (to the stationary observer) are many light years apart. This is reconciled by the fact that the crew's perception of time is different from the stationary observer's; what seems like seconds to the crew might be hundreds of years to the stationary observer. In either case, however, causality remains unchanged: the past is the set of events that can send light signals to an entity and the future is the set of events to which an entity can send light signals.

Distortions in time perception under pain have been widely reported, yet the mechanisms underlying these effects remain unclear. The Attentional Gate Model and prior empirical research indicate that attention and arousal are associated with pain and time perception, yet their roles remain unexamined in a unified framework. The study aimed to investigate the mediating roles of arousal, attention control, and attention bias in the relationship between pain and time perception. A systematic search of China National Knowledge Infrastructure, Wanfang, Web of Science, and PubMed identified studies reporting associations among pain, arousal, attention control, attention bias, and time perception. A two-stage meta-analytic structural equation modeling approach was used to test mediation, with multilevel meta-regression analyses examining moderation by age, gender, pain type, and target duration. A total of 154 articles (176 independent studies) were included. Pain was positively correlated with time perception, arousal, and attention bias. Both arousal and attention bias were positively correlated with time perception, while arousal was negatively correlated with attention control and attention bias. Mediation analysis showed that only arousal had a significant mediating effect. Moderation analysis indicated that age, gender, and target duration significantly moderated the relationships between attentional processes and time perception, with age additionally moderating the relationship between attention control and attention bias. Overall, arousal showed a mediating role between pain and time perception, while attentional effects are context-dependent. This study extends the Attentional Gate Model to pain and clarifies the roles of arousal and attentional mechanisms in temporal experience under pain. OPEN PRACTICES STATEMENT: This study was preregistered on the Open Science Framework ( https://osf.io/suzhn/ ). The data and code are publicly available online ( https://osf.io/3ucvb/ ).