“…Econophysics has also been used to evaluate the efficiency in financial markets, and it has shown that stock prices present a kind of long-term memory, which violates one of the assumptions of the EMH and the RWH. For instance, some authors have used methods and physics models such as the Hurst exponent and the detrended fluctuations analysis (Bęben and Orlowski 2001; Costa, Silva, and Ferreira 2019) to assess the returns, volatility, and behavior of tails distributions of returns in data, such as for cryptocurrencies (Dimitrova et al 2019), foreign exchange rates (Di Matteo, Aste, and Dacorogna 2005), and developed and emerging markets (Sánchez-Granero et al 2020; Zunino et al 2007; Balladares et al 2021; Cajueiro and Tabak 2005, 2004; Ferreira 2018; Ferreira, Dionísio, and Movahed 2017; Milos et al 2020), which evaluate whether there is long- or short-term memory in these time series. They used different trading strategies, reaching results that show that from time to time arbitrage opportunities arise for a short while and then disappear.…”